Thursday, 2 April 2020

The remarkable role of viruses in a new look at Evolution


Grey squirrels live in close harmony with a virus that is deadly to its rival, the red squirrel
Evolution is much more complicated than we once thought. Since the human genome was mapped it brought up all kinds of surprises and raised questions that had never been posed. Twenty years of intense investigation of the source and the action of genes just scrapes the barrel of new facts that are emerging.

My post today has been influenced by the book Virolution written by Frank Ryan. He is a no fly by night crank, he is an eminent research doctor at the peak of his profession. He is a world expert on research into disease and is on personal terms with all the great names at the forefront of genomic research. He lectures to eminent conferences and discusses his ideas with all the worldwide experts in this intensely researched field.
A surprising number of genomic researchers have discovered the most amazing things about genes and yet have not pieced together their evolutionary significance. Many are still steeped in the incorrect school biology that evolution involves merely natural selection, variability created by mutation and that all new species develop by slow steps in a straight line. 
His audiences warm to his interpretations and rapidly accept how their study and observations of our own genome are readily explained by a wider perspective and in particular the horizontal transfer of genes. Once thought to follow the rigid straight line of reproduction in family trees we now know genes are intensively mobile and even cross over from hugely different life forms. 
The cover of Frank’s book describes it as the most important book about evolution since Richard Dawkin’s ’Selfish gene’.
To pick out a few tasty facts our own genome contains only 1.5% genes of vertebrate origin and at the very least 10% of our genome is of viral origin. Facts that emerge every day suggest that latter figure might be very much more.
Only today I read that a new virus had been discovered where none of its genes were previously known.
You might guess that viruses are a very big part of my story today.

Disclaimer 
I would like to emphasise that none of my statements challenge that all life has evolved from primitive origins and the fact of evolution is undisputed (other than by the 50% of the world population who are misguided deniers). It’s just that now we have so much more knowledge than that which was available to my all time hero Charles Darwin.
A further admission is that The book Virolution although readily readable to the lay reader contains much technical information beyond my own ability or patience to completely absorb. I apologise if some of my ‘facts’ are not completely precise and others have become outdated before you read this. My aim is to indicate the direction of travel in new evolutionary thinking.

Hybridisation
Regular readers will know my obsession with the huge significance of hybridisation as an evolutionary force in genes crossing over and its role in deriving new species. It is astounding the sea change over the last few years in its general acceptance as integral in the evolution of both animals and plants. Frank Ryan presents it as a ‘given’ accepted by most ‘coal face’ geneticists that it has been immensely significant over the billions of years of evolution. 
The beauty of hybridisation is that it brings together thousands of new combinations of genes in a few generations. Most genes have multiple functions and many find new ones when hybrids occur. The phenomenon of polyploidly where gene combinations double or more, is often associated with fertility of hybrids and this process gives evolution much more to ‘work on’. 
Polyploidy is of course not unique to hybrids and genome studies suggest that two ploidy events have occurred in the millions of years of vertebrate evolution.
New realisations about viruses as an evolutionary force
To some of us it comes with horror that much of our own substance  is of viral origin and our integration has occurred throughout all of evolutionary time.

First a few facts about viruses.
They occur everywhere and have existed longer than normal DNA/RNA evolution. Ever since the first molecules were able to replicate they have been there - but always dependant on a host to complete their life cycle.
It has often been debated whether they should be classed as living. With a few tweaks on what defines life they certainly are and indeed the most numerous and successful forms of life ever!
They evolve far faster than life as we know it, most of their genes are new or unknown to science and have amazing properties and can perform functions which normal genes cannot. No wonder evolution has teamed up to exploit this remarkable source of variation.
Viruses achieve their reproduction by manipulating their hosts genetic machinery Being so small there is no part of the genome unreachable to them. Some readily share snippets of genetic code routinely, some have formed associations in the germ line as rare past evolutionary unions. To be honest I am out of my depth with all the possibilities of how virus genomes have teamed up with our own to achieve symbiogenesis and be as one with the original hosts

Symbiosis where things associate together to mutual advantage is not new to evolutionary science. It is accepted that chlorplasts in all plants originally came from a ‘captured’ algae and that our energy processing mitochondria were of bacterial origin. New thinking is that symbiosis has been a powerful evolutionary force not only in relationships between living organisms such as when fungus  and algae join forces to make up lichens but also in almost all aspects of our genetic inheritance. It comes as a shock that at molecular level the most common symbioses are between genome and virus!

How do viruses form symbioses with their hosts
Many ways are yet to be discovered but all start with the virus exploiting the host genome to complete its own life cycle.
My first examples is not very pleasant. Viruses start out as invading pathogens to a living organism. Sometimes they occur as a plague that wipe out almost complete populations of their host. Of course if they are too successful they wipe themselves out too and their is no evolutionary continuation! 
Take myxomatosis in rabbits as an example. The introduction of this virus wiped out almost but not all Australian rabbits. It was potentially good for those rabbits that survived - no competition. It was good for the virus because it had found a host with which it could co-exist and thrive and sustain itself. Most symbioses start that way and when each element adds to a partnership and natural selection follows. It’s all pure darwinian natural selection at molecular level. After aeons of time the original host might gain more than its original pathogen


Red squirrel susceptable to virus carried by grey squirrels
An example close to home is that of the grey and red squirrel in The UK. The grey squirrel carries a virus that is to the grey squirrel  harmless (and I only guess that it might make some symbiotic contribution). The same virus is lethal to the red squirrel and this is why in this country the grey quarrel is totally dominant.
Another little story from Frank’s book.
Because viruses have so many unique genetic properties and mutate fast they make rich partners in some of the very most sophisticated biological processes. The evolution all the placentas in those mammals that possess one has involved different but related viruses. Apparently their ability to form complex cellular membranes is a property unique to viruses and from traditional host vertebrate cells most unlikely to arise from the accumulated mutations of old evolutionary theory.
The genome itself clearly maps out to researchers how viruses were an essential part of the process

…and I dare not start on the consequences of viruses ability to jump from one chromosome to another …. and as already implied jump from one organism to another, archea to bacteria or even animal to plant

Epigenetics
The only new thinking that does not involve permanent changes to the germ line is epigenetics. Epigenetics is about switching genes on or off to enable specific functions. All living cells carry a full compliment of all the genes in a genome and now we understand more how they are switched on or off. Such activation is easily appreciated when you consider the ever changing differentiation as an embryo develops.
It is now known that epigenetic switches can be passed on from generation to generation - but don’t last ‘for ever’
When our own genome was first recorded scientists were astounded that only twenty thousand genes or so contained our genetic code. Much DNA was recorded as ‘junk with no essential function.This is now less clear and in many or most cases is wrong. Our viral inheritance is apparently closely involved with the evolution of all the above processes.

Corona

I wrote this several months ago before the scourge of corona and hesitated to publish as corona is so close to viruses role in evolution. I hesitated to publish but I am told that I should

Absence of posts
Regular readers will have noticed an absence of posts recently and will know that I have been on medication for acute anxiety brought on by destruction of half my garden by flood. I am not yet back functioning on all four cylinders but am on the mend and will tentatively start posting again.The good news is that the number of readers continues at its highest level ever!


Saturday, 29 February 2020

Companion planting, is it just tosh or is there something in it?

By all means mix plants together and avoid monoculture but read on...

It is all very complex
Companion planting is usually associated with pest control that arises from planting two or more different plant subjects together. The concept can be extended to the idea of plants being mutually beneficial to each other in other ways such as combined yield increase or giving each other a protected environment.
Both ideas can be flawed and in particular the first concept is supported by little evidence, gross exaggeration and wishful thinking and endlessly repeated myths such that companion plants need to be strongly scented. 

Except there are exceptions. Nothing in the fascinating plant world is simple.

As to the second concept, plant yield is usually limited by mutual competition for such as  available light and water. Growing for example a root crop among a leaf crop leads to lower combined yields than when the plants were grown separately.

I suggest that most companion planting arising from dedicated pairings or perhaps more commonly a ‘deterrent plant’ within a crop are a waste of time either because they are  completely ineffective or have only marginal impact which in normal practice is useless.

Take the highly popular belief that marigolds deter whitefly on such as tomatoes. Well they actually do - but not well enough. For me one whitefly is too many - on a plant like tomato which is so susceptible to glasshouse whitefly (indoors and out) a single whitefly soon becomes an infestation. Those who declare complete success with marigolds as a deterrent are probably good growers who do not insist on overwintering whitefly in their heated greenhouses on such as pelargoniums and do not introduce it into their gardens in the first place in Summer on such as their greenhouse propagated french beans. Without any companion planting I have not suffered from whitefly in twenty years. I would go so far to say that  my tomatoes have not encountered a single whitefly in that time (As opposed to brassica whitefly on my sprouts which is a different story)

You might be wondering why I have apparently destroyed my case by quoting one of the very few pairings, whitefly and marigolds where there is actually some deterrent effect! Indeed Newcastle University have extracted limonace (also the main oil in orange peel), the chemical actually responsible and have suggested it might be applied as a spray. To my mind spraying would be the kiss of death to the idea bearing in mind how gardeners seem to regard any spray as the work of the devil!

My example stands out as a kind of success story among other rather more useless popular pairings and my point is that a gardener has better things do than companion planting - except he might get pleasure from his illusions and might even like marigolds in his carrots. Actually marigolds are a fascinating plant and do produce root secretions toxic to eelworms and for certain plants in certain climates they might be useful - but in your own garden? Forget it.


I remember a bright intelligent student totally imbued with organic notions. He enlivened my lectures - not an easy task. His ‘plot project’ endeavoured to demonstrate the success of companion planting. With the best will in the the world we could not discern the benefits he purported to show. (But he won the plot prize)


I am indebted to Robert Pavlis whose latest post shines further light on companion planting. He shares much of my scepticism  and his post
specifically rubbishes the idea that it is scented plants that work these pest deterrent wonders. But first read this…

Evolved relationships between pathogens and plants
Is companion planting a waste of time?
Gardeners may feel that modern research which shows how plants communicate one with another -  often by scent - gives strength to the belief that scented plants confuse pest predators in companion planting. In fact it is very specific pheromones by which plants can communicate in closely evolved relationships where for example they warn one another about the presence of pests and consequently produce chemicals antagonistic to them. It does not follow that because plants have a strong scent they do the same. Our own senses do not discern a  plant’s subtle communications.
You might imagine that measures of natural plant self protection bear some resemblance to precise controls required by the gardener. Not so, there are subtle balances between potential pathogen and host. After all plant priority is to set a lot of fertile seed. It is not a priority to kill every last pest - that is too expensive to the plant’s resources.


To go further when you look at the plant world there is a spectrum between plants and potential predators which runs between complete symbiosis to total destruction. It is sometimes not clear whether an organism is an enemy or friend.
Why is it that such pests as red spider mite or whitefly cosy up to certain plants in abundance and yet other plants hardly suffer from them at all. Indeed one researcher asked why is it that most pests have restricted hosts and only attack vulnerable species? Is there anything in it for the so called victim?
It can all be represented as evolutionary combat.

It might be taking things a bit far to speculate why a plant might allow itself to tolerate a particular pest. A researcher suggested that aphids could be good for a plant in the wild that is in infertile conditions. Aphids drop honeydew which can stimulate nitrogen fixation in the soil. The plant effectively gives up sugar to achieve more nitrogen and thereby maximise its seed production.


My Solomon's seal missed the sawfly this year
I myself wonder why solomon's seal allows sawfly to decimate it so severely year upon year? Could it be that in late Spring it has completed its life cycle and hived away in its thick roots ample resources? It just might be a service for the tough leathery leaves to be chomped up into manure.


Why do brussel sprouts abandon their green leaves on old stems when attacked severely by fungus disease in late Autumn and yet the sprouts and the plant tops stay green? Is it saving its resources to fight the real battle?

You might very well ask what is all this to do with companion planting?
I am not really sure myself! It does illustrate that plant/ pest relations are complicated and most companion plantings are too simplistic and that nature’s aims are not the same as our own.


(If at this point I might put in a promotion for my next but one post. It is about symbiosis when organisms  evolve in harmony. New thinking is that symbiosis is a prime driver of evolution right down to genome level. Those of you have followed my series on evolution might wish to read it)


The appropriate/inappropriate pest landing theory

Thank you Robert Pavlis for reporting this elegant study at Horticulture Research International, Wellsbourne UK . I applaud this prestigious institute which in a previous guise was the National Vegetable Research Station. If you grow your vegetables in anything like a modern away you can be sure that their innovations play a major part.
In a series of elegant experiments they demonstrated that flying vegetable pests having generally identified the area of their host crop by scent from the air and are only attracted down to the ground by the colour green. Any green plant would do and even green coloured paper attracted the pest. They planted a wide range of potential companion plants around vegetables crops and all that were green attracted the pest. Any plants that were any other colour did not attract the pest.
The pest detects on alighting whether anything green is the appropriate host. If not it tries again on a nearby green plant. The more ‘false starts’ the less eggs will be laid. It was shown that any green ‘companion plant’ fulfilled this function. Conventional coloured scented ‘herbs’ performed poorly. There were several examples of vegetables that had lower pest loads when they had  green companions such as clover!

This might lead you to the correct conclusion that such as ground cover and weeds(!) would both satisfy this deterrent effect!
Hang on! Weeds might decimate your crop far more than pests and ground cover might reduce yields by competing for water. Take care not to draw the wrong conclusions from new discoveries!

Companion plants as a lure
I knew a dutch commercial grower of tomatoes who used a few pots of french beans in his glasshouse as a trap for whitefly. Each week he would remove the infected pots and replace them.
I have not time to discuss this principle today but will merely quote Robert Pavlis’s dry comment that his neighbours are only too welcome to plant them

Grow a wide range plants and avoid monoculture

Although I have been sceptical today about targeted companion planting I must hold true to my conviction that growing a wide range of plants in your garden is a fundamental arm of cultural pest control where diversity provides a myriad of habitats for predators of pests. In contrast farmers and commercial growers are stuck with large monocultures and find the need to regularly spray


Links

Robert Pavlis writes about companion planting

Peter William's  article on natural planting

Tuesday, 11 February 2020

Stress from the floods

Roger and Cathi's garden. It got much worse than this
Drain Strain September 2019
As I write this we have no idea how it will end. A huge lake has invaded our garden. It might be only 30 cm deep but it covers more than a hectare. It covers half of Cathi’s garden and continues on over her fields. Its total volume must be more than a million litres.
Each time in rains yet again the lake’s level rises by more than the rainfall. A centimetre of rain brings a rise of rather more. Each dry day there is no perceptible fall in the level. We have had a pump going that takes out thousands of litres an hour. I makes no difference. Imagine  emptying your bath at a cupful a day- or perhaps even by a thimble?
As I write at the moment I cannot bare to predict the harm to my garden. At present a fifth under water a further rise of  40cm will threaten our house. Already Cathi’s barn is under water. Every morning she wades across the mud to feed her old rhea stranded and isolated on the far bank.
There is still ahead of us a Winter of wet and little evaporation.
I cannot bare at this stage to elaborate on the measures we are taking to provide drainage.


It looks spectacular at times

Drainage theory
Let me step back to describe the fundamental principles.
Penetration 
Most gardeners are familiar with the problems when water stands and cannot penetrate through. The problem is usually puddling or compaction and gardeners often try to improve absorption by adding gritty materials and busting compaction.
This is not relevant to me as my soil is almost pure sand. Unfortunately  two metres down it is pure clay where further penetration is almost impossible.
A route for surplus water
This is achieved by buried drainage tubes and ditches. On a very small scale perhaps rubble drains. The problem of course is there must be places for pipes and ditches to go.
Water received from higher land
This can be very much more than the actual rain that falls on your land. We have that in diamonds  and are surrounded by higher land on three sides to the garden.
How long will things survive underwater?
About half my garden has been underwater
February 2020 The black dog descends
I don’t just mean the black stinking mess our garden became after six months of standing water but also the dark depression that crept up on me to the point that I am now on medication against acute anxiety. Brenda too struggles to hold us together. Its worse for Cathi next door. For months she waded every day across foot deep ever muddying water to feed her rhea stranded on the far side. Her shed is flooded and birds are trapped high in her henhouse. The ducks love it as each morning they swim outside. She struggles to keep her rescue hedgehogs thriving and cart out extra food to supplement the grass for her soay sheep.
It is only now I can bear to tell you about our watery nightmare. It’s not over yet but the end is nye. You might have noticed my posts have appeared less frequently recently. I have almost run through my stock and must write some more. I have just not felt up to it. Several further posts will be on the implications of this watery theme.

Things got worse after my first paragraph written six months ago. Our problem is that our gardens exist in what in Winter is a great big wet hole. Cathi and our own flooding has coalesced into a seven acre lake.
As we all know it just kept on raining last Autumn. In a two month period we had the rain for an average year.


Searching for the drain in the dry top part of the garden.
So much for no dig gardening!

Hitherto we have been dependent on a huge fourteen inch bore drain laid in 1940 by War Agriculture when constructing the then Melbourne airfield. It has become partially blocked over such long time. It runs down into the three foot slope to the top of our garden.
It goes under a fairly busy road at a depth of seven feet - and runs away to lower fields below


The horror of finding the under road blockage
We of course with the help of drainage experts dried to clear the drains. Our world came to an end when they found that re-metalling the road several years ago had almost completely smashed the drains.That is the only route to take the water away

Everyone told us being under the road made it the council’s responsibility!
Ever tried to get speedy work from a council whose maps show no drains at all! Cash strapped councils don’t do these things without prodding and ‘legislation’ and considerable time - which we did not have. We were told of a case where a council was successfully sued but the litigant was NOT awarded costs - more in lawyers fees than paying yourself.
We have asked a reputable contractor to do the work which as I write is delayed by administration!

A faltering step forward

By the time the lake had extended to seven acres Peter Williams and a local farmer John Rowbotham came up with a short term solution. John has a drain that crosses under the road two fields away from our flooded area and it has spare capacity. The farmer who owns the intermediate field (itself thoroughly saturated) kindly agreed for a drain to be cut across his land. Local drainage genius Robert Hunt braved the bog to cut in a three inch drain that leads into a temporary ditch that gives the water a route out. A ‘full pipe’ removes thousands of gallons an hour and yet it will still take a month to clear the water (And that assumes no more rain - some hope with a huge storm predicted for tomorrow)


The machine that laid the drains was very speedy and Robert managed to not get stuck in the bog
Temporary ditch runs water to the drain
After three weeks the flooded half of my garden is starting to reappear. Not so for Cathi where the water is much deeper. Heaven knows how many of my thousands of plants have been killed after up to five months under water.
I will be keeping you posted!


Six months ago - much worse was to follow in Cathi's garden
The very next day from writing the above it rained more than two inches - put us back at least two weeks

Wednesday, 29 January 2020

Plants that become weeds




Who wants a twenty acre wood of cardiocrinum?

Garden plants that take over

Horse radish is very difficult to eliminate
The press reported when Jeremy Corbyn gave Tom Watson horseradish plants from his allotment that it was a show of good will.
It was a poisoned chalice.

One of my achievements when I took on the overgrown Bolton Percy churchyard almost fifty years ago was to eliminate this weed. It had roots two spits down and roots as thick as my arm. It took two years of glyphosate spraying to remove it.
If conventional perennial weeds are allowed to stay undisturbed in the ground for a very long time they too become so strong that they are much harder to eliminate than the text books might claim and need extra applications of weedkiller. (Not always - a strong stand of undisturbed couch grass will succumb to glyphosate in one go  and as I previously described I eliminated many year’s of established and crucially undisturbed, convolvulus very easily in Steven’s garden).


Some plants have the capacity to build up their strength for year upon year if left alone. Have you ever tried to dig out a ten year old hosta? 

Left for decades  some plants will become  monsters. Witness Japanese knotweed originally planted in Victorian gardens and how now ten foot high plants rampage through a landscape. As a new individual plant it is a pussy cat and easy to control.


I do not want my legacy to be Equisetum hyemale taking over Bolton Percy Cemetery (I have already eliminated it)

Indeed I would go so far as to suggest some potentially problem plants are difficult to get started. Gardener have often told me how their lily of the valley just won’t grow. Others struggle to eliminate strong stands or slow its spread.
Some plants year upon year build up huge resources. Beware.

Books warn not to plant aggressive houttuynia. This one took several years to achieve 
It is not my intention to frighten you today. Quite the opposite. For myself I love plants that are tough and can take care of themselves. If they spread horizontally and fill up large spaces that suits me fine. I relish the spread of such as alstromerias and Autumn anemones.
This Autumn anemone makes seven feet on Bolton  Percy heavy soil. It struggles to three foot on my own sandy soil
Some folk fear alstroemeria because they 'run'
There are perhaps two main characteristics of potential rogue plants They spread horizontally and/or make deep root systems or other resistant perennial structures. 
Bluebells such as these would be very difficult to eliminate should you wish to do so 
I will almost ignore today those plants that take over by self seeding. 
Perhaps just a word about bluebells. From seed they are slow to come up to flowering and even from strong bulbs they take a while to make up to a decent display but once established are really thugs. Beautiful thugs and in Worsbrough cemetery cover huge areas.

Perfect storms
There is more to it when certain plants take over than having planted the wrong subjects or long years of inaction. A major factor is whether the plant loves your conditions. Things such as soil type and fertility, drainage and light conditions. Just as a good gardener goes out of his way to plant in the right place for maximum success, for some of the thugs you can have too much of a good thing!


Monty says never plant skunk cabbage, it might take over. Here in a bog at Bodnant perhaps after a hundred years they are somewhat over grown but look quite superb
I moved from a heavier clay soil to my Seaton Ross sand. I was overjoyed to grow plants I could not before.
It was a great disappointment to find for others I could not. My beloved Aster ‘Violet Queen’ now needs all my skills to maintain it. The Japanese anemones although still lovely only make half the height than in Bolton Percy. Achilleas, hepaticas, bulbous iris and echinacea just fade away. Phlox do well for me but take years longer to establish strong clumps. (On the other hand Phlox subulata creeps freely and is a sheer delight).

Several thugs that the garden gurus tell us not to touch with a bargepole are for me shy maidens and difficult to grow. I delight that my Houtonya spreads at all. I bought expensive skunk cabbage and after twenty years I rejoice that it is big enough to be noticed.


Horror story follows about this shy plant that transforms into a monster
An extreme case of a ‘delicate’ plant ‘going native’ is the lovely poppy-like herbaceous perennial Romneya coulteri (shades of Mrs Coulter in Phillip Pullman’s wonderful ‘Dark materials’). I just cannot grow it at all. Not in any of my very different gardens and I have tried several times.

Peter Williams received an appeal from Glasgow. I think about a well drained sandy light soil - I never saw it but clearly a dead ringer for Romneya’s native habitat. The lady owned  an old sandstone property which was being ravaged as the roots ate up the foundations. Every story you have read about Japanese Knotweed was mirrored and exceeded here. I am not sure whether my own advice helped the dear lady. I wish now I had taken more interest, helped her more  and got some pictures
Peter Williams tells me he does manage to grow Romneya. In the past with great difficulty. It is now making very strong suckers. Some garden threats lie there as sleepers.

Woody wanderers
It goes without saying that self sown and inappropriately planted trees create dense shade and damage foundations. Not my subject today.
Many climbers are woody and some can be a menace. 
I have written before how global deforestation often gives aggressive climbers and sprawlers a foot hold. In the UK too some become monsters.
Most of us have witnessed how aged Russian vines are a nightmare to remove and it might take days to cut away from old buildings.
More innocuous genera do have their monsters. Clematis armandii and passiflora caerulea  are both tender plants that in the North can be difficult to grow. Given space and time and absence of pruning in a warmer climate they are a real menace.   The ever popular Clematis montana  has its moments too.
Give wisteria several decades and your parkland will become a jungle.

Always think twice about planting bamboos There are some none-creeping kinds but for the others beware.


Peter Williams hard prunes his Kiftsgate every year. If he did not do so he would have a monster on his hands
When I had my own clients my dear friend Jackie Barber grew that rampaging rose, ‘Kiftsgate’. It is super vigorous, lovely, very thorny and will swamp even quite vigorous trees. I dreaded the uncomfortable prickly day that her single plant would take me to prune each year.


I have just returned from Madeira where it strangled one hundred feet cliffs - sorry forgot camera!
There are herbaceous stranglers too. For most of us ipomea is a delicate annual. In Vico Equense (my son lives there) it is truly  perennial and over the cliffs and adjacent gardens creates huge tracts of blue. Think of our own bindweed. Naughty but nice.

Bits and bats and bog plants
Give it five minutes and hippurus will take over a huge lake. (Carefully directed glyphosate easily zaps it in your small pond at home)
This section has a watery theme. Bog areas and ponds are particularly vulnerable to rogue plants going native. Plants that have evolved to like wet conditions just keep on growing in sunshine and on really good sites never lack for water and have little competition from regular plants.


Leucanthemum, the shasta day
We always take our umbrella when we go to see Rowena and Harry in very wet Preston. I mentioned this post to Rowena and she confided in her problem with leucanthemum, the shasta daisy with which she has a love/hate relationship. Their garden is on 30 foot deep heavy clay, there is heavy rainfall and water springs appear in awkward places. Many of the fine plants she puts in die. Her shasta daisies are lovely. (She has a beautiful white border and guess what is the dominant plant). It spreads everywhere  and even in relatively dry weather her clay soil generously sustains it. It is starting to penetrate into the mortar of her brick wall. For the moment the house is ok.
Dammit it has died out on me. To be fair to this vigorous plant I have only tried the poncey double and fancy-petal varieties. 

Back to  bog plants some of which are are prominent in lists of alien plants illegal to grow and some have prohibitions on selling and planting. 
Over the top but some aquatics in water courses are a serious menace.


My gunnera loves its boggy patch. I wonder what it would do if left untouched for fifty years
The answer to the above question is that its spread would cease when it met drier soil - or strong plant competition (I might be able in a few months be able to tell you what complete submersion for six months does to it - my garden is still half under water - drains now in place)


One answer to over aggressive plants is to let them fight it out with each other
 Aristocratic weeds
Peter and I attended a lecture that pictured a neglected ten acre site completely taken over by cardiocrinum lily. It really hurts your wallet to buy one. They take perhaps eight years from seed to flower and set seed before each plant dies. Absolutely magnificent but a nightmare to tackle. Its what you get after fifty years of leaving alone. They retail at twelve quid a  throw.
I suppose when your lake is taken over by water lily you might describe that too as an aristocratic weed.

I wonder if you have any other candidates? 

More about the Romneya nightmare
Peter Williams has furnished me with some of the details of his anguished correspondence. I pick out some of the details from the emails he shared

….the builders are immediately moving in here, as the house has been invaded by a nasty, vigorous plant from the garden which is growing between the plasterboard and the masonry in the dining part of the kitchen. 8ft high and 3 ft wide. Has 
entered from garden under the bottom layer of our 6 layers of flooring insulation…… 
….Romneya coulteri, an American poppy, but not just any old poppy. A poppy on steroids. As well as having to have the kitchen dug up (and we don't know how far it has spread in the house), we then also  have had the patio slabs lifted to find out where it has entered the house, and then most of the large border excavated to eradicate it between the patio and the far end of the garden… 

….We hope the inside work will be finished by Christmas, but don't yet know if the outside work will start immediately or will wait until the spring. It has also spread into our neighbour's garden, who, like us, have been cultivating it assiduously as it is a very beautiful, large showy plant with lovely huge white flowers in late summer. No sign of it in their house, though…..

…… Not covered by insurance, as this has been gradual and not an "event". It was planted by the previous owner of our house, who was an avid gardener. It is very difficult to get it established in UK, as it likes desert conditions, but she managed it! …..

What a nightmare

Sunday, 12 January 2020

What makes a gardener?


What greater pleasure than to breed a new plant
I don’t mean what makes a successful gardener, I mean what makes many people just want to grow plants. Some of us are so besotted we think of nothing else. I write about both gardeners at home and those who dedicate their whole professional lives to it
Is there a ‘green gene’?
I wonder how much our love of growing is genetic. Clearly some of us will have characteristics that predispose us to it. But is there some arrow perhaps shot when some of our hunter- gatherer ancestors started to sow and plant plants?
Involved in horticultural education I would interview young people whose sole desire would to be gardener. 
On the other hand mature students would declare their long desire to garden even on their retirement from another profession. 
 
Alan Warwick  - equally proud of his spuds

My friend Alan Warwick - I wrote about the Chelsea apple tree he bred and his insightful theory about how water gets to the top of a large tree -  was a very senior ICI executive who on his retirement enrolled on my one year craft gardening course, bought a small nursery and now thirty years later at ninety one gardens all day.
No dig gardener - digging? (No just lifting)
In my own case I got the bug at the age of 14. Up to that time weeding my parent’s garden was an unwelcome chore and not a joy. We moved to a new house with an overgrown garden and as I have written before, my parents (to my juvenile mind) did not have a clue or inclination what to do. I took it upon myself to restore the  garden. It was digging out couch grass and the smell of the soil that turned my green gene on.
The pleasures of gardening
I thought it would be easy write about the joy of gardening. Not so. For every gardener it is something different. For every gardener there is a different garden
Gardening is a spectrum running from pure hatred to a reason for living. It runs from intense physical activity to easy gentle reflection. It contrasts precise manipulative garden maintenance to communion with nature.
Best give a few examples

* I know a lady whose idea of pure heaven is to lie in a warm bath and study a seed catalogue.

*I myself fall asleep thinking of what gardening I will do next day or mull over the future of what I have started
The thrill when a difficult plant flowers

*Gardening brings moments of pure joy. The first time you see new roots on a cutting will bring an ecstasy never to be repeated although always bringing huge satisfaction. A first new flower on a precious plant just the  same.
 
And cooking them too

*Eating your first homegrown tomato. You own vegetables however manky will always be delicious.

*The feel of fresh air and solitary reflection.

*The creation of a new or changed garden in your own image

*Transforming in a day by hard labour a weedy patch into a beautiful picture. (A way of gardening that I myself do not approve)

*Watching an ever changing image as the seasons unfold or merely when a dull patch transforms as the sun shines

*The allotmenteer who leaves his worries behind and meets his mates.

*The warm feelings when you share your passion and/or show off your garden

*Getting your hands dirty and the smell of the soil

*The endless progression as you learn something new

I love this quote from The Garden Jungle by Dave Goulson 
"My garden is a little corner of the earth I can control, small enough to comprehend where I can make things right"
What makes a good gardener?
It does not really matter.
A very good gardener
 When I set out to write this post I had the intention of offering a few pointers to what special attributes a good gardener possesses. When I started to list these features it all fell apart. They don’t hang together. Superb gardeners proceed in diametrically opposite directions. 
For every attribute I can think of, I go to a good gardener who is different
Brenda gardens when it is not wet, windy or cold
I would like to think I am a good gardener myself and yet every day Brenda tells me how I am not
Perhaps the greatest thing about gardening is that we are all different and so are our gardens and the pleasures we get from them. You can be a garden lover - even an expert - without lifting a finger!
Some gentle scarifying?
Perhaps a universal attribute of really good gardeners should be that they recognise the skills and endeavour of others. Things might not always be to their personal taste but quality shines through.
(Except that a few are  scathing and intolerant. Gardening for some brings out our worst competitive instincts)

Where wise men fear to go fools step in. So purely for your entertainment here is my opinionated offering of things that make a good gardener
Sue Garrett is a superb gardener and a brilliant blogger
Doing jobs at the right time - not only on a seasonal basis but day to day decisions,  Is it dry and windy?  -  hoe. Is the soil wet? - plant (not if you are a fluffer). If it is a still day consider spraying.

When doing routine maintenance don’t just tidy for the day but consider long term development. 
Inspection time
A good gardener’s plants will be healthy. He might never spray but by doing things right his plants grow well.

Understanding watering. It takes a good while to learn. You get to the stage that just a casual glance will tell you a plant is in need.

Listen to advice but make your own decisions and always be prepared to try something different.

Love you soil, even if that means leaving it alone. All soils are different and your own deserves your understanding

For many gardening tasks such as weed control a ‘little and often’ approach might be best. (not for watering)

A good gardener listens to his plants and treats them accordingly

Be generous to others. The best way to preserve your plants is to give some away.
Just as well I gave Peter Williams this rare dicentra

In the last month of his life philosopher Franz Kafka with terminal TB retired to the country. He said he had never known such happiness as tending the garden at that time.

Links

Read how Alan Warwick raised a sensational new weeping tree

Learn the correct name of that yellow dicentra

 

Wednesday, 1 January 2020

My throw and grow colour kaleidoscope - Year Two


The problems of continuity 

An early splurge of orange - other colours followed
Last year I posted about my new hardy annual feature and if you missed it, it is best to read it now.  (You will be able to click back)

It was naughty of me to call it a meadow.  It is really just  a hardy annual  border but one managed on naturalistic lines. I did mix in a little fescue grass but it was completely overgrown.

There are several things I want to pick up on, not least how local authorities might differ from the home gardener in their management  bearing in mind we gardeners are there everyday to pounce on a stray weed whereas municipal gardeners are never there. After all it is supposed to be low maintenance. Dream on.

Many recent and very popular municipal roadside displays of direct sown annuals really are magnificent and in the first year are no bother at all. I wonder how they manage continuity from one year to another.
Do they need to resow? How do they tackle the inevitable perennial weed that will establish? Do they dare use glyphosate between seasons on what are (wrongly) perceived as natural features? How do they tackle the prolific annual weeds such as fat hen, sow thistle and shepherds purse that grow and self sow so freely amongst the colourful flowers - potentially becoming worse every year. Perennials such as nettles readily self sow too if allowed to do so.


This fat hen must not be allowed to self seed!
On my own patch I will describe how this year it was almost completely self sown - I did not sow fresh seed other than a few whimsical extras. How long can I continue before some subjects are lost and the more vigorous becomes dominant?
On a different note I observe Peter William’s perennial wild flower meadow each year changes its character.

I was lucky that in April and early May the soil surface was constantly wet and the seed got a superb start. Nature sows more densely than I would ever do. A very good thing and if the odd seedling got trampled if I pulled out a weed or aimed a delicate spray no matter.


A touch of colour in Lyndi's field
In contrast I scattered some seed in Lyndi’s field in early May when unfortunately the soil was starting to dry and germination was poor. On a small patch at home gardeners might choose to water if the weather turns dry. There might be ample water in the ground to sustain growth but insufficient surface wetness to get the seed started.

Weeds

A few large weeds have been hand weeded away
In this my third season there were more weeds from seed than before.
In my half-hearted first season in what had previously been my vegetable garden managed with my ‘no dig; and ‘no weed seeding’ methods I had an extremely clean start in terms of absence of weed seed. The annuals were broadcast as is my normal practice - unlike traditional methods where in conventional hardy annual borders the clumps are usually sown in seed drills to facilitate hoeing.
It was easy that year to hand pull the odd weed!

I do feel that the ‘throw and grow’ seed mixture was not immune from weed contamination and in the next year I did find certain new weeds resident in my garden. I must have missed them in the first season and they took to their new home.
When you have solid masses of flowers it is much more difficult to stop weeds seeding. I try my best but even I miss some and I anticipate possible problems in future years.

I find that seeded nettles thrive in my ‘throw and grow’ regime. This year and last I have spot-treated small clumps of nettles with carefully directed glyphosate. Quite easy as you get into Summer and some of your flowers start to ‘go over’ and the odd trampled annual grows on anyway! (Indeed I twinkle through the display to pull a few carrots on the far side)

When I pull out my weeds I just throw them down to desiccate and die. Although my annuals are on very fertile ground and in theory might be better on soil of less fertility I am unable to break a habit of a lifetime of enriching the soil by casting down weeds! Where a large weed has slipped through and is already prolifically seeding it is best to remove it!
At the end of the season and before new self sown seed starts to germinate from March next year one has a completely free run for easy weed control! Do not neglect this opportunity to tackle all weeds.

The flowers

 
As previously mentioned they are (mainly) hardy annuals and not native wild flowers. They very well might be if I had originally chosen such a mixture. Peter Williams observed today that some of the annuals might very well be another country’s wild flowers harvested from meadows.


Not in the original seed mixture these short lived perennial violas sow themselves
Actually I found my mixture was not wholly hardy annuals. I have spotted a few biennials and a lovely orange wallflower two years ago held on to flower in the next April among the new seedlings.
Today in October I spotted a few cosmos which in my book are half hardy annuals.

Bold commelina flowers up to each lunchtime
My own variations have also intruded and have self seeded in amongst the melange. Lovely short lived perennial commelina adds splashes of gentian blue. A few dahlias wandered in last year and proved to be hardy. I will this time deliberately scatter some more. 

Self sown dahlia in its second year
That lovely annual grass that Brenda constantly harps on about when it self sows in other parts of the garden is in there too.
Anyone know what this invasive foxy grass is called?
Last season from May was hot and dry. Many of the flowers had after three months completed their life cycle. Ever tidy Isobel whilst admiring the flowers, delicately inquired what I do with the strawy dead yellow or brown stems. It would be easy to pull a few handfuls out - and indeed some found their way to Lyndi’s field and Cathi’s verge as seed sources. 


Late germinated alyssum pervaded the whole plot with a scent of honey
Late Summer rains brought new germination. A refreshed white carpet of honey scented alyssum was an Autumn joy and dwarf nasturtiums came into their own.

Nasturtiums and second flowering of Salvia horminum
Calendula also comes into its own in late Summer

Winter management
In Autumn of the previous year year I had mused how I would clear up the debris at the turn of the year and how hard it would be. I should not have worried, the strawy remains frittered down to almost nothing. It was work of just a few minutes to rake off shrivelled vegetation and leave any promising seedlings and still green plants.  I had a clear run to spray off any weeds and up to March this opportunity continued.
I wonder what local authorities do at this juncture? A York roundabout which had had a very successful season looked rather scruffy in December but not untoward. I expect that in April they will remake a seedbed and resow.


Myself I shall yet again do zero seedbed preparation and just wait for my annuals to emerge. There will be copious seedlings but will they maintain a suitable balance? Perhaps I will top up with a few favourites? 
And when should I sow them? New self sown seedlings start popping through in March

Originally from the farm field corn marigolds will be back

Link
My original post when I stopped growing most of my vegetables and scattered a few annuals
 
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