Wednesday 24 February 2016

Some tips about ‘spot’ glyphosate spraying

Much ado about nozzles

A tale about nozzles

My much loved knapsack sprayer is like an old teddy bear, rather battered and frayed. I have never really understood straps, belts, braces and buckles and my fumbling fingers don't properly tie shoelaces!  Brenda constantly nags me to hitch up my trousers. 

After many years the lower strapping on my knapsack was becoming detached from its mounting. Originally my Berthoud sprayer was of the all singing and dancing kind. Now the up-market so called comfort lower strap was anything but and got in the way. After several months of discomfort I had the brilliant idea to cut it away.

It’s a long drive to Barnsley when I go down monthly mainly to spray. It’s somewhat disconcerting to arrive and find your nozzle is blocked. No liquid squeezed through. I took out the nozzle and confirmed that the pump was working. A nozzle is only a hole in a bit of plastic, (oh no it isn’t). I dare not tell you how I tried to unblock it. I admit trying a thorn. 

It temporarily cleared, but some attached frayed plastic or something unknown immediately re-blocked it. Disaster. And then I remembered that in a small pocket in the strapping when in a moment of wisdom I had foreseen this very event I had secreted some spare nozzles. In that same instant I also remembered that I had cut it away!
My time was not wasted. My general incompetence has taught me to have second options. I had taken my ratchet loppers, my petrol driven hedge trimmer and a sharp Irwin Universal Jack Plus 880 saw (no one rewards  me for this promotion).
I spent my time cutting back herbaceous perennials, tree suckers and a weedy understory of holly, yew and other saplings.

My temper was not improved when rather fatigued I arrived home. I went to the Agritech website where I had originally purchased my Berthoud sprayer. They offered a fine range of nozzles. I wanted the yellow cone type and selected a packet of three. I went to the basket and found part of it a curious grey. I assumed that when I filled in my details it would go black and the none existent ‘continue’ button that I was told to press would appear.
I wasted five minutes. Unfortunately it stayed grey. I must have missed out a detail? I wasted another ten minutes figuring out what was wrong. In the end in frustration I went elsewhere. I admit in my ill temper I had difficultly in finding a suitable source. Beyond caring, I did find a blue cone kind and bought it. It came the very next day. As soon as I have finished my writing todayI will find out whether it is OK!

Of course I eventually realised that I was greyed out because my order was too small. I understand that, but why don’t they tell you. The loss to them of my order is nothing, nor is my meagre good will. To me my frustration was immense. At least had I been told....... I would have probably bought an extra packet or searched the site for something extra.
I was completely unfair to Agritech who are an excellent company. I later test-tried to put a single nozzle in my basket and a ‘pop up’ told me my order was insufficient. So perhaps I am just too stupid to sort out that grey

More serious stuff
Most gardeners are pretty vague about nozzles and sprayer calibration. Me too.
To a farmer extreme accuracy is needed. Not only does it hit them in their pocket if they overdose even by small amount they also have very varied covering requirements. For example they will need a fine spray to cover foliage difficult to stick to; a coarser spray to spread soil acting herbicides and a remarkably coarse spray to apply liquid fertiliser. Equally important are legal restrictions on dose rates of chemical. A crucial difference to the gardener is that they are spraying a uniform crop all over and they need to apply a known amount of chemical.

This might be useful…. or perhaps not?

There is an enormous amount of technology relevant to sprayers and their nozzles. The matter of most interest to gardeners is the size of the hole and to this end they are colour size coded. And there I was thinking they were just pretty pastel shades in a mixed packet! 

A small hole gives smaller droplets. An increase in spray pressure will give increasingly fine spray. The smaller the hole the further the sprayer will last before it is empty! 
Unfortunately most of a sophisticated system of technology, regulation and training is of little value to a gardener!

What the gardener needs

Almost all the spraying I do is of the spot spraying, weed killing kind. I direct my spray at the weeds and the accuracy I need is to give each weed enough weedkiller to kill them and by my skill in direction not to harm my plants. So critical to the professional, who blanket sprays chemical over a complete crop, the dose per unit area is  completely irrelevant to me. Other than to avoid breaking the law or doing something really stupid.

The best approach for the home gardener is make up his spray to a strength appropriate for the actual weed problem. My scientist friend Peter almost always sprays at a one in fifty dilution of commercial  360 gm/litre glyphosate to water. I myself make up mixtures in the range between one in fifty and one in a hundred.

When I spot spray my gardens their are a great number of variables. These include the density of weed cover, nature and size of the weeds. 
In my cemetery gardens there are paths, gravestones, trees and weed free soil. Within reason all are avoided. In many areas wanted plants cover large patches. My actual spray covers a very small portion - perhaps 10% - of the total area.

The village plot is about half of an acre and the only weed control is by spraying

I recommend gardeners invest in a professional knapsack sprayer. For a serious user of glyphosate anything less is a cheap toy. And yes I do admit that I controlled all the weed in Bolton Percy cemetery with a small and less accurate hand sprayer for several years and when I visit family and friends use whatever is on offer!
My knapsack takes fifteen litres of water. Now in my dotage I only fill it to ten litres. The village plot is about 1800 square meter. Depending on the variables mentioned and also my mood and the season I complete my spray with between a third and a tankful. I admit the day I started the village plot ten years ago when it was a sea of ground elder and nettles it took a little more than my full fifteen litres!
When I go down to Worsbrough cemetery my ten litre of dilution usually covers between 1500 and 4000 square meters. It depends on the weeds! It will normally take me an hour and a quarter to empty my tank. I give this as a guide to a new user playing with pure water to sort out his technique and his nozzle.
My garden at home is one acre. Regular readers will know I am a plantoholic with thousands of plants, many rare and often packed together. In early Summer when my plants are maximally vulnerable to misdirected spray it takes me three to four hours to spray the complete garden. It might take two ten litre spray-fulls and I maintain the necessary intense concentration by splitting my time. In that time my garden is as a result completely weeded. In contrast in Winter when most herbaceous perennials are dormant and weeds are sparser I spin round in less than an hour and perhaps use a third of a tank. 

I cannot imagine the time it would take to effectively control weeds in my garden if I did not spray. I would have no time left to look after my plants.

My spraying technique includes a range of pressures between one pull on the handle, a mere squirt, to perhaps three pulls for a larger collection of weeds well away from the plants. My pressure is a mere fraction of the sprayer’s potential (or the pressure used on a spray course designed for farmers). I vary the distance of my spray head from the weed according to circumstance, the closest almost touching. My nozzle usually points down although I will also angle it away from my plant.  I let my spray head hover a little longer over a difficult weed. I try to avoid spraying to ‘run off’  - other than on rosette forming weeds such as epilobium. Unless my weeds are close together when I maintain my squeeze on the handle I otherwise interrupt the flow with the spray trigger.

I have been playing with my nozzle

This density of cover might be typical

This block has been lightly sprayed. Not in one swathe but more like colouring a picture

You can be very accurate with practice 

I can’t quite spray on a sixpence (my yellow nozzle would have been less coarse)

Best to keep the spray head moving for accuracy
Providing the nozzle is nearly touching the ground and the pressure is low you can safely take out this cleavers and coarse grass without harming the bulb. Remember glyphosate is translocated and it is not necessary to cover the complete weed.
And the nozzle?
Although the anvil type is generally recommended I do not agree and always choose a cone one. You might prefer to buy a mixed packet of nozzles and try out a few. The nozzles are normally universal and not manufacturer specific. I am giving my new blue one a go for a few sessions. If I find my tank is emptying too quickly I will order a yellow one!

And how did I get on with my blue cone nozzle? 

Very well so far and I have used it several times. The real test will be Worsbrough. It’s hard work for an old man hoisting a full sprayer on his shoulders and I do not want more than two fills on a visit! If a ten litre fill does not get me as far as I expect to I will be straight back to yellow!
In testing my new blue nozzle I knew that it would deliver too much liquid if I did not reduce my pressure via less pumps on the handle. I actually tried one thrust on the pump handle - no more than a squirt and rather a coarser delivery than I normally require. Because of this posting I put my pumping hand in my pocket to see how long the flow would continue. It did not stop! That surprised me! The flow is of course stopped when the trigger is closed.
For devilment I sprayed the whole garden on gravity flow. As my main weeds at this time are small rosettes of the wretched epilobium it was ideal. 
I normally expect to pump harder to achieve a wider ground coverage and a finer spray distribution. In the large more weedy expanses at Worsbrough I might pump it three times. I of course let the pressure subside before pumping again!

And I have now been back to Worsbrough
With herculean effort and steely concentration I pumped a little less than I am used to. There were several clumps of Winter germinated cleavers and the usual small clusters of epilobiums, tufts of coarse grass and larger digitalis plants invading plant clumps. A range of spraying patterns were needed. The blue cone nozzle passed with flying colours (well blue ones). My tankful lasted one and a half hours and it covered well over an acre

Which one works for you?

If you use the glyphosate links in my theme column there is a complete course on spraying

You can read about my trouble with machinery here and here.

Friday 19 February 2016

Four petal snowdrop

Is this my lucky year?

More on March 2
I am triple lucky I have found two more! Thanks for the tip Rick they are four tepals and not petals!
I have spotted this form previously in this clump of snowdrops so it is not a just one off occurrence. One of the pictures is the normal three petal form from the same clump

Wednesday 17 February 2016

Are gardeners too precise?

Do your sums in the garden but fussing about is a waste of your time!
It might even be detrimental

How on earth can I calculate the area of my lawn?
Many years ago  the UK ‘went metric’ - did it really happen? What acutely annoyed me was how newspapers and gardening magazines would give dual recommendations with imperial numbers translated with great accuracy to metric. For instance, the legendary four ounces per square yard might appear as 135.6 gram per square meter!
How silly! Did no one tell them that 4oz per square yard was a hugely rounded figure, itself an estimation arrived at in someone’s fevered imagination? Even a sensible ‘scientifically precise’ recommendation would normally be equally valid plus or minus, lets say, twenty percent!
When you consider the extreme variability of diverse gardening situations where measurement is needed, even differences of several hundreds of percentage points usually works!

Take fertilizer as an example where a rate of 4 oz per square yard used to be often recommended for growmore. I confess I might myself sometimes think in these terms and reasonably make a mental calculation to half the rate to 2 oz per square yard when estimating my stronger and superior Yaramila which has a somewhat different ‘balanced’ analysis.
But on what is my rate of fertiliser application actually based? Apart from the fact that it might be be a marginal decision whether to use any fertilizer at all? There are so many variables! The real need depends on the soil analysis, the physical nature of the soil, the nature and condition of the plant, the time of the year  - need I go on?  At best when I apply my fertilizer it is a ‘ballpark’ estimation. I vary my rates of application of fertilizer based on my so called ‘experience’. I hope I am right more than I am wrong. The good news is that when I am wrong, unless I have done something completely ‘off the wall’ it won’t really matter! If I apply too much nutrient most will still be there for my plants next year.

A blogger recently asked in a gardening forum how much sulphur he needed to reduce the pH of his soil from 5.7 to 4.8. He was seriously deluded that you can turn the pH on such a sharp pin! Tables of recommendations state figures for different soil types such as ‘sandy’. There are hundreds of subtly different sandy soils. The best answer to the blogger’s question admitted a ‘fudge factor’ of 100%. No one asked him why he required such an extremely low and precise pH. I disingenuously asked him what he was growing. The answer came back as ‘blueberries’. I had egg on my face in that about pH 5 is probably optimum for this crop.
You would be amazed at the methods used in the States to acidify soil!

I have a history with iron sulphate. When I wrote my post about it, it went down like a lead balloon! Now it is by far my highest statistic and had been read 50,762 times at 5.13pm on January 20th! How’s that for a failure to ‘round off?’

In that post I quoted an application rate of 10 gram per square meter for moss control in a lawn. This was my conversion from a quarter of an ounce per square yard, perhaps a ten percent ‘error’? I really felt quite brazen when my son’s photograph showed me flinging iron sulphate around. My inaccuracy in distribution is yet another consideration!

But where did that figure of a quarter an ounce come from? For my sins I once used to check copy for ‘Gardening Which’. I remember my glib satisfaction when I spotted the spelling error, ‘forget-me-knot’!  I also remember querying the rate of application for iron sulphate as between 1/4 and 1oz per square yard, thinking the latter figure a typo. I never found the truth about this 400% variation!
In actual fact when I apply iron sulphate - to control moss rather than just as a general improver - I deliberately  apply it unevenly. Where the moss is thick, perhaps where the lawn has been shaded by a flower border, I scatter more. This wet season some of the moss has even been sphagnum which is even more of a challenge. I suspect a few patches really do get 1oz per sq.yd. They need it!

I am confessing all today. When I find my lawn mossy I just go to my 25kg bag of iron sulphate and scoop some out into a suitable carrier and go out and chuck it at the mossy places. Retrospectively as I was writing this post I calculated how much I must have applied when I moss killed last month. It was just over a quarter an ounce per square yard average over the whole lawn area. But then I am a regular user, perhaps three times a year (notice the vagueness) and my moss is not all over.
This brings in another factor, one’s power of estimation!

Having a fling
Spraying weeds 
My most accurate work is with my knapsack sprayer. It is most important that I kill my weeds and not my plants. To this end providing an accurate uniform dose per area is of no concern whatsoever although this concept which is  legally and practically necessary for farmers, might provide a beginner with a rough guide.
My weeds are widely scattered, vary in density and nature and are selectively sprayed. My rates of chemical applied per unit  ground area are very much less than the amounts calculated for an overall application.

The concept most useful to gardeners is the strength of spray in their tank! My scientist friend Peter accurately makes up his spray tank for almost all of his spraying at a fairly strong 1 in 50 of commercial glyphosate to water. I (accurately and deliberately) vary my own  between 1 in 50 and a very weak 1 in a 100. 
My measuring bottle lives in my tank. The strength on the day depends on the weeds - stronger for nettles and epilobium, weaker if tiny weed seedlings are dominant. It might also vary a little with the weather (might it rain?), temperature and season. In practice it will usually be between 1in 60 and 1 in 70. My fifteen litre tankful of spray will cover as little as seven hundred square yards or as much as an acre. It depends on the weeds! For example if I meet a clump of  ‘difficult’ ragwort in Worsbrough cemetery my nozzle hovers over it for a split-second more.
It might amuse you that I use metric units to calculate my spray application and yet have strayed to square yards and acres in the above paragraph!

In my next post I have trouble with nozzles
This use of estimation and my apparently cavalier attitude to exactitude hide my ernest desire to do what is best for the garden. Recognition that ‘variables’ occur and that nature itself is not only very resilient but ‘plays the odds’ against environmental vagaries leads, me to speculate further about how excessive accuracy might not be the best way in the garden.

Take the depth of a seed drill. Obviously it will vary with the size of the seed and you might have some insight as to what is appropriate for your soil.Take it as evidence of my slovenly nature that my drills are never completely straight and I don’t use a string, board or line!
But other factors are at play. A deeper sowing might be best in dry weather. On the other hand if it is wet a shallower drill may be better aerated and if it is very wet certain seed might be better if not covered at all. At the time you are sowing you cannot read the future.  Am I just lazy or merely taking an each way bet when the uniformity of my drill does not pass muster?

Planting bulbs is another case where extreme variability in depth and usually failing to insert upright will often not matter. In my recent post I mentioned planting 1800 bulbs on Cathi’s new verge in a total time of about three hours. (Note that my posts are littered with qualifications such as ‘about’, ‘almost’, ‘often’, ‘sometimes’ and ‘maybe’. Brenda says I never make up my mind). When I plant bulbs I lever up a spadeful of soil, and without further disturbance tuck several bulbs under! Some might happen to be upright but most will be horizontal. They all grow and flower and thrive. By the time they flower their second time around all bulbs will be upright and nature will have decided the depth they prefer.

In actual fact nature herself plants bulbs very erratically indeed. A dense patch of snowdrops pushes surplus bulbs out of the ground. Not to mention rabbits that with the help of the wind, distribute them around where they root and grow. That’s how they spread naturally without any help from the gardener!

When we moved into Boundary Cottage I had a stupid prejudice against the Carlton daffodils dotted around the garden. I forked out the dormant bulbs and scattered them without planting in rough stubble on the roadside verge. They made a magnificent clump which continued for the next ten years. When the road was relaid and the edge was grassed down even though chopped and churned they just carried on

See what the rabbits did in Cathi’s garden - I have lost my best picture that showed hundreds which I scooped up to plant in her new verge.

But what about my provocative subtitle which suggests excessive accuracy can be a bad thing?
It was rather ‘tongue in cheek’ and usually the greatest damage of too much precision is spending precious time faffing around and neglecting a more urgent task in another part of the garden! 
If I were to ‘rake up’ some examples they might include amateurs messing around with next-to-useless soil analysis products bought at the garden centre. It is fifteen years since I needed to use a pH test and I have never had my soil analyzed. Perhaps I should? Regarding professional analysis done for you by a laboratory the real genius is to correctly interpret the information you receive.

Striving for uniformity raises my ire. When I weed kill my lawn I follow the weeds. When I spray my borders I refuse to spray at a constant pressure as is often recommended. It does not apply to the spot spraying I do. When I fling fertilizer I have no need for a distributer. Peter commented only last week how his spreader had clogged up yet again and he had once more needed to buy a new one. 

What is the point of applying water mechanically and uniformly in a greenhouse when all the plants need different amounts?
Fun in Funchal
We have just returned home from our holiday in Madeira with botanist Mike Ashford and his gardener wife Isobel. We met up at Funchal botanic garden with Peter Williams and Julie who were there on a walking holiday. Knowing I had just written this post I thought it too good an opportunity  to miss to test them on their powers of garden guess-timation.
When viewing from above I asked them to estimate the area of the garden's signature rectangular carpet bedding.

Funchal’s manicured carpet
Peter immediately said 900 square meters, he says he got there by mentally visualising his own lawn of known area. Mike was more  reticent and made no disclosure. On hearing Pete's suggestion I immediately halved my own to one third of an acre!
We agreed to go down and pace out the area.

Imagine the three old fogeys from ‘The Last of the Summer Wine' pacing this crowded place. Diminutive  Welsh Peter striding and determinedly pacing. Me and Mike diffident, pretending to be just walking. Mike nearly fell off the wall. I did not ask them if their strides were metric or imperial.
The width was easy. One could guess it was twenty metres and round off our strides. We all agreed twenty meters. The length was a smidgeon more demanding but we all came to seventy five meters giving an area of one thousand five hundred square meters.
If our effort proves anything it is that pacing is usually good enough for gardeners!

When I was at college our tutor asked us to debate whether horticulture was an art or a science. I still don’t know the answer.

Wednesday 10 February 2016

Contemplating compost

The limited action of adding nitrogen to activate a compost heap

A holiday postcard from Funchal
Sometimes you learn something that truly astounds you. This research review is dated 2008. I am grateful to Robert Pavlis on The Garden Professor's Facebook website for bringing it to my attention. It is real serious science that brings together sixty separate investigations.

It is common knowledge that adding nitrogen in the form of a fertiliser or as a nitrogen rich manure activates and speeds up the rate of decay of garden compost. It turns out that this is only true of soft vegetation - which is the stuff that decays rapidly anyway. The rate of breakdown of the fibrous stuff such as straw or herbaceous tops or woody prunings is not effected in anyway other than adversely.

The technically minded compost buff talks about nothing other than carbon/nitrogen ratios. Soft stuff such as young weeds and fresh mown grass might be twenty to one carbon/nitrogen proportion. Herbaceous tops are perhaps seventy to one and are very slow to decay and this is generally explained as a result of low nitrogen content. Thirty to one ratio would seem to be optimum.

It might take several years to turn fibrous material to compost. 

Here in the 200 year old  Blandy Garden, time scarcely matters when they eventually dig out wonderful fine stuff

They compost all the organic material they are collecting
Regular readers will know I do not have a conventional compost heap! I know one of my gardening heroes writer Ken Thompson writes that he needs to have a 'serious conversation' with anyone like me! I protest that I recycle all of my organic matter albeit directly.

I never have weeds to remove as they desiccate in situ after spraying with glyphosate, hand pulling or hoeing. All my mowings are scattered by my mulch mower. The worms bury my leaves and the toppings and tailings on my vegetable patch. Most of my dead herbaceous tops are shredded into little pieces by my  hedge trimmer and left on the ground. I bury newspaper and sometimes wood or woody prunings. My bulky prunings are burnt in such a manner to create masses of everlasting charcoal.

The nearest I come to composting are heaps of herbaceous tops from areas of the garden supervised by tidy Brenda or tops too bulky to shred and perhaps organic debris from my ponds!
On such piles I have generally flung a little general fertiliser to 'improve' the nitrogen ratio. It would appear I have been wasting my time. Well perhaps not entirely as the organic matter will retain the added nutrients for the future and the soil below will beneficially absorb them.

In Funchal Botanic Garden they bury their tough organic matter
Peter Williams is a very keen composter and he is preparing an article for me on how he goes about the process. Now that will be really interesting.
Robert Pavlis noted on Facebook that it was only he and I that had taken any notice whatsoever of Robert's own startling revelation. The impact of this knowledge seems to be one of deafening silence.

What is the significance to gardeners?
Probably very little. Good composters will continue to mix together high and low nitrogen containing material to the benefit of both. Or even all three if you include the happy composter himself!

Gardeners will continue to compost low nitrogen fibrous material  and such things as privet hedge clippings. After all although it takes much longer to decay, such vegetation makes the most valuable and long lasting soil organic matter and, dare I say, humus!
Gardeners like me will be happy for still fibrous material to be mulched on their soil. My gardener/botanist friend Mike, will continue to re-compost his incompletely decayed fibrous vegetation a second heap around.

I wonder what Peter will say in his post about proprietary  'compost activators'. Are they just useless or merely a complete waste of time?

Links to further reading
Robert Pavlis wrote about organic gardening and glyphosate.
The Garden Professor is having a spot of bother
Ken Thompson has been composting tea bags although Harry Kennedy points out that they should not go into worm bins.
Robert Pavlis is dubious about egg shells although Tony Cuthbert isn't
I wrote about burying wood

You might discern that I have just returned from two weeks in Madeira. I will be showing rather more floral pictures soon!

I expect at our Eden Mar hotel the weed goes in the bin!

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