How to grow Zantedeschia

Mainly about hardy Zantedeschia aethiopica

Little did I imagine twenty years ago when Steven married Haley and the bride carried Arum lilies which also bedecked the tables that I would ever successfully grow these magnificent cut flowers. At that time I lived in dry Bolton Percy and without using copious watering they would never have thrived. With regard to watering I used to be rather self restricting and if an established  plant needed watering in the garden I felt it to be not worth growing. That included vegetables down on my allotment.

Now in my Seaton Ross garden zantedeshias are littered everywhere and make magnificent strong deep rooted plants that add brilliant white to the garden from May until September. My very deep sandy soil overlies clay that creates a water retentive basin. A huge ancient agricultural drain takes surplus water away and half of my garden boasts that rare condition of all year round well-drained moist soil.I have more than a dozen randomly distributed two to five foot high zantedeschia specimens. 

(Whoops I have written too soon and this August we have run into quite severe drought! My plants look healthy, some are setting seed but there will be no flowers for next month’s Open Day)

My Open Day guests will not be admiring my Zantedeschia ‘Crowborough’

Zantedeschia aethiopica ‘Crowborough’ is an almost fully hardy bog plant that can also be grown in a pond as an aquatic. I have doubts about its long term success in open water but it will certainly survive through the Summer! I would be very interested to hear of anyone who grows it permanently in the water. I tend to think that bog plants such as this arum and my own ten foot high gunnera prefer to be planted next to water but just a little above it where their roots can penetrate down.

My gunnera gets plenty of moisture but never stands in water - other than occasional Winter flooding

French interlude

My pictures of Brenda’s son’s zantedeschia in France provide some evidence of their permanent success in very shallow running water. They are absolutely six foot magnificent. The ancient traditional public laverie spills spring water into a very shallow stream that runs across his land. Needless to tell you I brought a few very small divisions home. With patience very small pieces after a few years made wonderful huge plants.

The water drains from this still used laverie

When Peter moved in I took several divisions from this plant that had established itself naturally and dibbed them into his stream

They soon established and now hold their own against Peter’s brambles and nettles (this was a good day)

In the water they make luxuriant shiny foliage 

and look very fine

Culture of  Zantedeschia aethiopica

The French variety has found my own garden to its liking

The methods of growing the hardy Crowborough variety and similar cultivars is very different to those for the widely available more compact coloured tender hybrids which I will consider below.

'Crowborough' is really quite hardy, especially when established. Mine survived the notorious 2010 ‘double Winter’ with minus eighteen centigrade air temperature registered in both January - March and December. Just!

Very small plants like the one I brought back from France get going better if you give them greenhouse protection for their first Winter.

They thrive in moist soil although many gardeners successfully grow them in ordinary deep  well drained soil. They are best undisturbed and go from strength to strength with each succeeding year. My own grow in a wide range of conditions but the plants in full light do the best.

Although the books correctly tell you that you can lift and divide them this does give the numerous propagules a considerable check. I prefer to notch or tease out pieces with a spade leaving the parent little disturbed. Small pieces can be potted for coddling in a greenhouse and larger divisions can be directly planted. My plants rarely if ever go completely dormant but are best divided in Winter or Spring. For the record my French rooted shoot was taken in August.

Your established plants need plenty of space when they will make strong large specimen clumps.

Do they respond to fertiliser? Are they better with mulching or adding extra organic matter? Probably yes but I never bother. Do they get pest and disease? I have never noticed - except the tiny black insects that show up on the flowers.

Should I let them seed? Probably not and I remove the dead flowers to encourage more. Do they need staking? No.

Growing the coloured hybrids

For fifty years I had ignored the coloured hybrids that are sold as ‘bulbs’ every Autumn and Spring. Early failures with rotting-off tubers and weak spindly growth when directly planted in the garden persuaded me that they were a complete waste of time. Especially so when I knew them not to be Winter hardy and be best started off early with artificial heat. 

Although I do love our heated conservatory, artificial heat for greenhouses has never been the way for me. Many texts wrongly quote rather high minimum starting temperatures as essential for these so called callas. That might be appropriate for commercial cut flower growers but not for me.

Brenda’s son Steven lives in balmy Folkestone and his coloured zantedeschia is permanantly established in the ground

Last year I decided to try some coloured calla cultivars in my unheated greenhouse. ‘Unheated’ is a bit of a misnomer as so called cold greenhouses heat up very well with the sunshine. Even better the warmth is suffused with healthy light. Artificial heat in a greenhouse on dull days very early in the season is not usually a good  gardening option!

I am still on my learning curve. In researching this post I learned that these coloured zantedeschias like it rather drier than the hardy species. Especially when starting in their pots and before new growth appears when the roots can easily rot. Like any plant that grows luxuriantly when they get going they then need plenty of water.

I  grow them in large pots of my own sandy soil enriched with slow release fertiliser and regularly top dressed with my yaramila general fertiliser. Most gardeners chose to liquid feed. My plants are stood outside throughout the Summer.

An advantage of tubs is that they can be temporarily placed next to a wide range of plants

I have fallen in love with these coloured hybrids.

Less strong first year plants bulk up each succeeding year. In my second year I have not chosen to divide them.

I overwintered the dormant tubers last Winter, still in their pots almost unwatered in my unheated greenhouse.

I think I was lucky as it was a very mild Winter! I have written before how I lost tender plants in containers in the 2010 Winter when for example agapanthus survived outside in the ground when those in the unheated greenhouse died. I am confident that my tender zantedeschias would survive in the greenhouse in a normal winter but in fear of a harsh one I will this year overwinter the tubs in my almost frost free garage.

My niece Gail recently admired my coloured callas and reminded me that they were her wedding decoration too.

They seem to be rather popular at weddings

I wrote about growing agapanthus last year

Tree Work

A not so peaceful day in Bolton Percy Churchyard

I knew that villager and very fine arboriculturist Jason Brown had submitted a very generous tender for extracting four very large trees from the cemetery. It was by complete chance when I arrived for my monthly stint - a little early at nine  - to find the road cordoned off and Jason swinging like a monkey halfway high up the enormous Leylandii. Already it had lost the bottom half of its branches? Neatly cut and precisely dropped direct to the road.

Could I get in to spray? Jason’s two lads in perpetual motion were dragging and thrusting  branches into the shredder. They stepped aside to let me enter through the squeaky gate. Not that you could hear it today. The chainsaw and shredder created quite a cacophony.

Immensley  professional, Jason was safely strapped to a strong secure sling on the tree. I was later impressed how he zipped up and down the fifty foot monster. I could barely climb that high if I had the rest of the day.

I later confessed it was I that had forty years earlier planted the tree! Not only that but I had rooted the cutting on my allotment. That year I was very keen on the rooting properties of horizontal shaded polythene laid over cuttings inserted direct into the ground. I had propagated hundreds of plants - fortunately very few were Leylands! Three had gone into the cemetery and their removal was Jason’s task for the day! A passer by overheard my admission and enquired if I felt at all sentimental about the tree’s demise. No, I was absolutely delighted.

It had been very foolish of me to plant them at all. No one should plant such potential monsters in a cemetery. I recently blogged about conifers as a habitat for wildlife and suggested that gardeners might plant certain varieties and be prepared to fell them several years later and plant some more. 

But forty years that’s ridiculous! Perhaps I should offer to pay? I hope my forty years maintaining the garden will be my contribution.

Blogging in mind I took a few pictures of the rest of the garden. Unfortunately the sun was  very strong from the wrong direction. I remembered when Marianne Majerus came to photograph the garden she was up at six in the morning to get the light the right way. Ah well I would get some more next month and publish later. I would have pictures of the finished job....

Every year Clematis fargesioides and wild honeysuckle are in friendly combat

The agapanthus has been there longer than the Leyland Cypress

Garden plants grow naturalistically

I received an e-mail that evening. Unfortunately two of the other trees housed wasp nests that would need to be destroyed and a pigeon had a nest... somewhere. Tree work can be dangerous enough without wasps buzzing around you! The job is partially completed. Progress was slow as the gravestones are a real problem. The first tree will remain for a while as a totem. I will publish today and add pictures of the finished job later.

We will be left with some fine planting opportunities  - so much more light and moisture.  The thirty year grouping of Rosa ‘Nevada’ that has been in steep decline as the Leyland has got bigger will rise like a phoenix.

We are going to be left with a wonderful mulch pile. A job for the ‘C team’!

Tree work in pictures

Large trees need to be dismantled. Not just chopped down. This was the stage when I arrived - about half an hours work

The lower branches were dropped in the road

The shreddings will be used for mulching in the churchyard. They will reduce weeds from seed and not in this case be composted

This Leyland cypress is the next one to come down

You can see the large thuja down the churchyard path. It is probably a hundred years old. It has grown very little in my time and is becoming unstable. Due to its venerability and species it has a better public image than the Leylands and will only be beheaded! 

Forty foot high Jason is safely secured

I was intrigued how they would take the head off the Leyland and would need a picture. Sadly the operation was done so quickly I missed the opportunity! I could not envisage that an arborist’s accuracy is such that they can drop a trunk on a pin head. A few deft cuts with a small chainsaw and the top fell precisely into the road. 

I was getting my camera out, Jason shouted “ten pence for the picture” as the top fell. I dared not tell him I had missed it!

Ten seconds later I was ready!

Even Jason surprised himself at the size of the tree

I wonder if this totem will be there for my next visit. I would have liked to have seen  the trunk sections coming down,

I left for home at lunchtime. The two rounded tops of the thuja are now gone

Open day announcements

As a working churchyard the cemetery garden can be visited at any time.

This notice is about my own garden at Boundary Cottage

Tuesday August 23rd. Next week! Open in aid of Yorkshire Arboretum. Open all day including evening. Refreshments only served between one and four. Peter Williams has agreed to open his very fine garden down the road (from 1pm) and no doubt his wonderful plants will be on sale. For those without the bumper all garden ticket from Yorkshire Arboretum the entrance will be five pounds. It will cover those who want to add Peter’s garden

Boundary Cottage yellow book Open Day is on Sunday September 11th. Directions are on the NGS website

NGS directions to Boundary Cottage

NGS directions to Peter's Garden  Weathervane House

(You have missed his NGS Open day!)

Link to Yorkshire arboretum website

My recent post about birds and conifers

My post about Marianne Majerus's visit and a route to her own website with pictures of cemetery

The cemetery 'C team' gets to work 

Boundary Cottage this morning

Update ten days later
Thank you Jason you have done a great job for the village

The job took all of three days. It looks like a further planting opportunity

Finding out about no dig

The things they say

I said recently that I do not like to repeat myself. Well not very much. I have written extensively about why I don’t dig and good and bad reasons why others do.

People might come to my website to read a man who calls himself a no dig gardener and find very little about no tillage. My purpose today is to tell you where to go - in the nicest possible way by following links! 

I do this by discussing what people say when they come to my garden. Relevant links are at the bottom

“The garden must have been dug when you started?"

Some visitors barely accept that I don’t need to turn soil over and have no concept that when I made the garden I did not need to dig it at all. 

Actually that is a small lie. In limited places paper, wood and stones have been buried and to attain levels some soil has needed to be shifted. For instance previous owners did the typical amateur thing in cutting out borders lifting away turf or perennial weed creating sunken ill drained litter-collecting formal rectangular hollows. The best soil was in piles littered everywhere even in the field over the wall. At least it had not been thrown away in the wretched green bin!

I cannot guarantee that previous gardeners never dug  but sixteen years ago the overgrown weedy mess had not been cultivated for years.

I agree the true amateur would be unable to make any inroads into making a garden without seriously disturbing the soil. Those who are more knowledgable but who misguidedly reject spraying with glyphosate also find it very difficult to avoid cultivation. Although it is not impossible, I doubt that they would manage on my own ‘industrial’ scale.

All the glyphosate stuff can be referenced from my theme column. I recently posted about starting out on Cathi’s overgrown grass/nettle/ground elder verge using glyphosate with no soil disturbance at all.

I have previously written how digging or ploughing or rotavation speeds up converting an overgrown patch to something visually pristine. But at a cost of future perennial weed problems. Not to mention that digging is very hard work.

My stainless steel border spade

“But you have a sandy soil”

There is an alternative to this...

“I can’t do no dig because I have sticky clay”

No dig has least to offer on sandy soil. Because sand has a coarse texture you will cause little damage if you walk on it or work it (perish the thought) when wet. As long as you don’t drive over it with a bulldozer. 

My own sandy soil has a peculiar property, it is hydrophobic and repels water when dry. Worse from my own point of view as a no digger if a border is raised and uncultivated loosening the surface actually aids rain penetration. I confess an argument for digging! I have written before about how I prevent my own water running away. My fine sandy soil is actually very water retentive if thoroughly wetted. It ‘wets up’ nicely when the soil is contained in a rimmed container.

This fern has thrived in a plunged twelve litre pot of my sandy soil for four years now

This Spring I planted some more

And disguised the pots with a mulch

No dig has most to offer on heavy clay.

Clay soil brings all its problems when it is regularly cultivated and an endless cycle of breaking up exposing it to the slaking action of rain (not to mention the oxidisation away of binding organic matter) and subsequent rock hard setting or in wet weather the formation of doughy clarty mess. The problems are caused by cultivation which leaves structure exposed to damaging rain separating out fine clay particles red in tooth and claw. I have compared this to a junkie getting his fix but going nowhere.

I once developed several very large borders for my friend Jackie Barber. She lived in Pottery Lane and neighbour Roley made the finest clay pots from their extremely sticky clay.

I just sprayed out the borders in her grassy paddock and in this case mulched with her copious supply of mushroom compost. Thanks to Jackie’s superb design skills and lovely plants from her nursery you have never seen better borders. Other than very small planting holes there was no soil disturbance at all. After a year or three the soil developed a beautiful black honeycombed crumbly structure. You could walk on the border and even plant after heavy rain.

I do sometimes go a little far in deriding veg growers on clay soil who dig. Where allotment holders really go wrong is where plants are exposed to a soil regularly degraded of organic matter by excessive cultivation and dubious removal of vegetation and not adding very generous amounts of bulky manure, compost and recycled green.

“Its compacted”

He approves of loose soil

Gardeners do not understand compaction. Nor do much of the horticultural world!

Compaction occurs when loose soil is compressed when wet. It occurs most commonly as plough or rotavator pans but also anytime when wet soil is driven on by heavy machinery. Clay soils in gardens are the most adversely effected by compaction which is caused by the gardener walking on loose wet soil or worse cultivating wet soil.

Compaction should not be confused with the settling of a soil to a natural density. All my no dig gardens gardens have soil which is firm and cohesive to walk on and unharmed by normal compression.  Even when wet. When examined (with a spade!) they are honeycombed with channels and spaces made by roots, natural cracking and worms. Their drainage and aeration although as always limited by soil type and site conditions is superb. If further disturbed they break into beautiful crumbs. Of course your demonstration speeds their destruction.

Undisturbed for decades the soil at Worsbrough cemetery crumbles when dug with a spade

After a few years none dug allotments although similarly firm and settled (no need for silly raised beds) are black with organic matter and as a result of accumulated worm casting make superb seedbeds. I do argue the benefits of planting plants rather than sowing seed direct but for such as carrots I can even broadcast-sow as few weed seeds are brought to the surface by digging.

My leek seeds do not need to be sown in rows to facilitate weeding

“You need to aerate the soil in your borders”

You will know this if you read gardening articles written by apprentice journalists given the gardening column on your local newspaper.

The worms do it for you

It always amuses me that in ornamental borders to give extra aeration you are told to loosen the soil and in effect to chop up the roots. This is no joke in Autumn - especially if your drainage is dodgy - when surface roots are a lifeline when deep roots die in Winter because it is too wet.

I repeat if your surface soil is compacted it is a consequence of frequent excessive past cultivation and is not a result of failing to cultivate at all.

It is a moot point wether stirring such compaction lets more oxygen get to plant roots. It certainly lets more oxygen into intimate contact with broken up soil aggregates such as soil crumbs. Ergo binding organic matter is lost as it is degraded by oxygenation.

I won’t bore you again with the lovely soil structure with it’s own air delivery system and micro-piped drainage that develops when the surface soil is left alone. Plants grow and their penetrating roots infiltrate the soil.The soil receives organic matter from plant debris and root exudates of organic liquids. No-diggers never have problems with poor aeration.

“How do you get organic matter into your soil without digging?”

It’s the worms dear boy, it’s the worms.

None dug soil can be mulched with compost, well rotted manure, bulky organics and recycled fresh vegetation. Nature incorporates it for you.

In actual fact as long as nature’s on site organic products of photosynthesis are recycled  directly or indirectly as compost after several years of none digging the soil will be black with organic matter without importing any organic matter at all. 

It is a common delusion that gardeners need to improve their soil by buying in organic matter. In truth they are often replacing the organic matter they have destroyed or taken away. That is not to say that gardeners converting to no dig cannot speed up the process by mulching with imported bulky organic materials. 

Links to previous posts that discuss matters ‘in depth’

Sorry about the pun. ‘Dig in’ to these articles at your leisure!

I develop a garden on Cathi’s verge without digging 

Converting to no dig

Improving soil structure

Root damage by digging

Cultivating brings weed seeds to surface

No dig makes for healthy plants

Preserving mycorrhiza

Myth about aerating soil

Digging for a quick result

I jump on wet soil

Hydrophobic soil

Exposure of soil to frost

I dug in manure at Christmas

Explanation of difference between soil structure and texture

Understanding clay

No digging on Foggathorpe clay

Wonderful worms

Plant establishment without digging

Planting on wet soil