Tuesday, 29 April 2014

Hardcore Gardening


Gardening on rubble


When buildings and roads are constructed they are built on firm foundations of rock, concrete and stone.It is frequently deep and often compacted. This ‘hardcore’ is essentially stone. Wherever I see derelict remains of buildings and roads I see weeds. Nature has provided numerous plants with  the characteristics to survive and thrive in such conditions. Substitute interesting and beautiful plants for the weeds and you have a new garden!

After each of the Ice ages much of the Earth surface was rubble, rocks and moraines. Most of our plants in their turn in ecological successions have colonised such stoney foundations and over the millennia fertile soils have formed. Many plants like natural rocky outcrops and have root systems well adapted to grow in deep, sharply drained substrate. Numerous plants have remained  unchanged from those that thrived on early prehistoric stoney landscapes. Some of our garden plants do better in hardcore than anywhere else!

Some plants have been inadvertently preserved over thousands of years on a succession of man-made stoney foundations. Richard Mabey in his fine book  ‘Weeds’ charts vegetation’s preservation on ruins and ancient classical monuments. When they weeded and destroyed the rich 2000 year old resource of 420 documented wild plants on the Colosseum more than 150 years ago he portrays this vandalism as a crime against antiquity. In Mabey’s words, professional archeologists scoured more history from that great monument than any story that could be told by the mute stones.

Hardcore is not always deep and if ‘normal’ plant roots are able to grow through it there is often fertile soil below. If given a little help with a fork or a crowbar and perhaps by infiltrating some compost or soil not only will our regular plants grow well, some might do even better than normal. Plants such as clematis and hollyhock love a free root-run deep and wide within a water conserving mulch of broken stone.

When as a retired lecturer I was re-employed for a day to help with a student landscape project I casually stooped down and planted a plant in a gravelled hardcore path. My former student who was directing the project gasped in astonishment when his former soil-management lecturer stooped so low to abandon his soil! I expect next day they lifted the plant. There have been many cases since then I have planted amongst rubble and stone.

Case 1
A former client had the stoney foundations of a former outhouse on the north side of her house. It was a weedy eyesore. My attitude to redesigning a garden is to convert ugly features into attractive highlights and this was a garden with a great deal of potential. The hardcore was only about 50cm deep and planting holes could be broken with not inconsiderable effort. It was infinitely more to my taste and energy levels to plant into this than to replace the stone!  My penchant for planting small plants made my task relatively easy. After planting with all manner of plants, many rare and including herbaceous perennials, dwarf shrubs, alpines, bulbs and many self seeding plants it was mulched with an attractive builder’s gravel. It was perfectly practical to pop in extra plants later. Almost all the plants thrived. Some such as wonderful celmesias, I have never seen better.

Case 2 Lillian’s border


When Brenda’s mother died ten years ago I planted a small border in remembrance, at her sister Angela’s home. A farm hardcore drives goes close right up to the side of the house. I bought three dozen small sturdy alpine and creeping plants from out favourite nursery at Reighton. It’s a lovely ride for us to the seaside plant centre over the Yorkshire Wolds. Better for me to plant potted plants than divisions from home as I would not be there to regularly water them during their establishment. I broke up the hardcore deep enough to enable root penetration to the soil  below and planted in a strip perhaps eighteen inches wide. Each time we visit every two months or so, I spend ten minutes maintaining the plants. I sometimes take my sprayer to eliminate the weeds although more usually than not, I just pull them out. Some of the plants now have spread further over the drive. I suspect the farmer looked askance at the idiot planting into the road. I notice now that our antirrhinums have seeded over to his side of the road and make a beautiful display

Case 3 My border at home


The back of my house faces south and provides me an opportunity to grow tender and rare sun loving plants. A small length of the border has extra heat  which escapes from our coal fire on the other side of the wall. The  original ugly concrete four foot wide footpath had to go! I chipped out the concrete leaving the thick hardcore in place . The overhang of the roof provides excellent shelter for a dozen or more hardy cacti. Covered with gravel, the rubble joins seamlessly into my gravel mulched rock garden. The window cleaner still has plenty of spaces to walk on the gravel and we can enjoy special plants hugging the base of the wall. Plants grow there that would not survive anywhere else in my garden. The plants include Cyclamen cyprium, nerine, dendrathema, vallota, dwarf alpine primulas, Dicentra cucullaria, Corydalis solida, yellow brodea, Sternbergia lutea and numerous dwarf bulbs, many ‘difficult’ and some rare. Even Begonia sutherlandii thrived for four years until the 2010 double Winter. In Summer when I water my tubs I also give my partly sheltered border a drench.



Do not confuse my gravel garden with a hardcore garden, although sometimes they may be much the same!


The Scarborough lily, vallota is not supposed to be hardy. Mine conveniently flowers every year on cue for my Open day, the first Sunday in September. It even survived the 2010 winter!

Brodea ‘Yellow Star’ sends up its flowers after the leaves


Case 4 Bolton Percy Parish Room yard.
Bolton Percy Primary School closed in 1949 and became the Parish room. The old tarmac playground remains undisturbed (other than my plants) to this day and is covered by a deep mulch of sixty years of leaf litter. Now rather crumbled the tarmac only needs a sharp chop with the spade to insert cuttings or plants which can then spread and self seed in the cracks. Many are wild flowers. It is a wonderful shaded habitat for woodland plants such as hellebores and ferns. I planted a lovely Amelanchier canadensis in ‘Tree Planting Year 1973’ and added in 2000 the village Millennium tree, Sorbus ‘Joseph Rock

Case 5 My roofless roof garden!


At the bottom of my garden a very large concrete slab covers an old well. Too difficult to remove, I covered it with an old carpet (!), two inches of soil and the shards of excavated stones that I bring home from my  monthly maintenance visit to Worsbrough cemetery garden. Such an environment is only suitable for a limited range of mainly succulent creeping plants such as sempervivum and sedum. It does keep me in tune with trendy fashions and as the concrete block is a barrier to the capillary-rise from the high Winter water table below, my succulents are not drowned. Adjacent, I have created a raised rubble garden higher than the occasional Winter flooding. You will not by now be surprised by now to hear that I buried beneath it an unwanted 1970’s stone fireplace!

Case 6 Mainly climbers at the foot of walls and the house.

My house is more than two hundred years old and concrete surfaces, tarmac drives and posh paving has been repeatedly laid by former owners. We like to have climbers and wall shrubs on most of our walls. As long as one creates planting holes deep enough for roots to thrust through the rubble to reach the soil and/or loose hardcore below, once established, such plants will thrive.  Newly planted plants  need  a little cosseting to get them going. The very deep concrete at home needed a builder with his noisy concrete busting gear. He had to be very well supervised to make sure he broke all the way through the concrete. Builders tend to think that a shallow depression is all plants need!
My very best climbing yellow dicentras particularly thrive tucked at the base of the house wall surrounded by loose paving.

My mixed planting of a white and pink chaenomeles is not quite as intended but they both grow very well. 

Cultural notes
If your rubble is full of perennial weed such as couch and bindweed you will need to use a translocated weedkiller such as glyphosate before you plant. It is nye on impossible to eliminate such weeds in any other way.

Roots grow deeper and wider than most none-gardeners think. Some  will explore for many metres. As long as roots of normal plants can reach wet soil they will thrive. If adjacent horizontal mineral surfaces are porous they will provide a wonderful water conserving mulch. If impermeable concrete stretches a very long way you may have future cultural problems when the spreading roots permanently dehydrate the ground.

Most of my rubble gardens do not receive extra nutrition, but some do. There can be greater benefit to gain by scattering general NPK fertiliser over the stone than when plants are just in soil.

Covering hardcore with gravel not only looks nice but increases the opportunity to establish plants from seed.

Nature has had very little help here.

The only help these self seeded plants have had from my sister Marilyn and husband Dave is pulling out a few weeds.
I love sempervivums. They looked fantastic in the wall of the holiday cottage where we recently stayed

Not a surprise, wallflowers like walls!
Valerian was the star at Chelsea two years ago. Here together with toadflax it costs a little less!
The village plot still has the foundations of two old stone cottages

Aubretia likes walls too

Sunday, 20 April 2014

Why does my blue Corydalis flexuosa die?



How to grow Corydalis flexuosa or perhaps try Corydalis elata instead!


About twenty five years ago this exciting new herbaceous perennial was introduced from China and created quite a stir. I used to help man the Askham Bryan College stand at the renowned Harrogate Spring Flower Show. Each year people would depart through the gates with armfuls of this wonderful plant. They were almost  all destined to die. (The plants I mean, although we all go in the end!). We used to call certain subjects ‘nurseryman’s plants’ because they were easy to propagate and were so beautiful that when the customer wrongly blamed their own incompetence when they died they bought some more. People catch on and you never see Corydalis flexuosa at the show anymore. 

Before writing this post I thought I would check out existing cultural advice on the world wide web. There is nothing to tell you why they are difficult to grow! 
The key factor is that they need to be grown in a pot. Then they are easy! My pot grown Corydalis have flowered freely for a six to eight week period between January and May for twenty years now. (It depends on the winter weather exactly when it comes into flower). Every time I try popping a few in the ground they die the following summer. Now here’s the thing, all my tub grown plants are outside throughout the year and contain merely my own fertilised acid garden soil.

When I lived in Bolton Percy, where the soil is slightly alkaline I grew them in tubs of multi-purpose peat based compost fortified with extra slow release fertiliser. I understood at that time that my blue corydalis needed acid soil and I omitted any lime. This is not confirmed by the literature that says they can be grown on acid, neutral or alkaline soil. I wondered why such advisory sites just do not  just say the pH does not matter! Perhaps they don’t know?

What is special about growing in pots? I have concluded that it is regular  summer watering that prevents them drying out. In late Spring Corydalis flexuosa dies down and goes dormant for about six months. Their  perennating vegetative structures are shallow surface rhizomes, These are extremely delicate and if they dry out the plant dies. We get long periods of irregular drought here in York but my pots of dormant plants in my little nursery next to my greenhouse get a splash of water every time I water! In the open ground when dormant, one forgets where they are and neglects to water them when they need it. Worse, as I have explained in a previous post my own sandy soil is hydrophobic when dry and the water runs away, but significantly not in pots where it is retained by the rim and soaks in.

You never stop learning in gardening. In writing this post it occurs to me that if my reasoning is correct and my success in pots is because the rhizomes do not dry out in summer then there might be another answer. What if I plant Corydalis flexuosa under a two inch gravel mulch? A little project this year! Hot off the press I have noticed today a small plant flowering in the leaf litter of an emerging iris in my bog garden. It has ‘well drained moisture’ and is covered by a natural organic mulch.

I have cheated with this picture, this is the very similar Corydalis elata. It shows dying rhizomes exposed on the  soil surface. With elata they form in winter and they are usually deeper. It  is best to spread a little extra soil over them if they are exposed.

Two years ago I did a couple of lectures in South West Scotland where it rains quite a lot and the well drained soil is water retentive. My host had a beautiful clump of flexuosa in the open ground. Later on, on my busman’s holiday, I noticed some at Calley Gardens at the foot of a moist north wall.

I teased C. flexuosa sprouting rhizomes apart in late December and later published the photograph of a rapidly growing clump at the end of January. I regret to say my plant was rather swamped by the emerging hyacinths that flowered in March.



 C.flexuosa amongst the Spring bulbs

Corydalis elata 





This plant is almost identical to flexuosa but is twice as high and grows well in the open ground and is a normal, easy, long-lived summer flowering herbaceous perennial. My own are in moist soil and full sun to medium-heavy shade. It is a much easier plant than flexuosa but does not have the advantage of flowering in late winter.

The book says they may be carefully divided in spring, Is this what they mean? I divide mine with a sharp spade any time I fancy.

The hybrid between flexuosa and elata is of median height and flowers well through the summer.

The rabbits have tried to help me divide my corydalis but have done no serious harm!

Other corydalis

I am very fond of all corydalis, it is related to dicentra of which I hold the National Collection.
The genus is a much larger one than dicentra, it is genetically close, looks similar but has a much greater range of colour. Corydalis may be annuals or short lived perennials and their lifecycle may be dependant on seed or vegetative structures such as tubers, rhizomes and roots. Most of them are easy to grow. Some unfortunately are too easy and seed everywhere.

Corydalis chelianthifolia has delicate fern-like foliage, seeds itself  freely but only if you have well drained soil (or gravel or a wall!)


Brenda banned lovely Corydalis lutea from our garden because it seeds too freely. I grow it in Bolton Percy churchyard garden where it loves to seed in a wall!

There are many fine named varieties of Corydalis solida available when you buy your Spring bulbs. If they like you and you have freely drained soil they will come every year.

This warm spring, the above pink Corydalis solida has set seed. The seedlings will be variable but I am dying to try them!

This is the ‘wild-type’ of Corydalis solida collected in a chalky Cotswold garden fifteen years ago where it so liked the conditions it had taken over. At home it has merely seeded enough to give me a dozen clumps!

Corydalis ochroleuca is common, lovely, very free seeding and somewhat invasive. The plant on the label is very rare - if it actually still exists - and looks completely different. Dicentras are frequently mislabelled in public gardens. I must send them an e-mail. 

In common with the rest of the UK their Dicentra eximia is actually Dicentra formosa!


My own Corydalis ochroleuca seeds everywhere. Brenda would have banned it had she known! 

Dicentra cucullaria flowers at the same time as Corydalis flexuosa and also likes pots!

Saturday, 12 April 2014

Garden myths discussed: do you need to clean dirty pots?


I also make special reference to damping off disease.

Blogger Sue Garrett recently challenged fellow bloggers to publish pictures of less flattering parts of their garden. If you believe this picture was specially staged you are wrong!

I try in my blog to provide correct factual information. When I fail to do so please let me know. Inevitably in some cases there is a degree of speculation and opinion. You might decide that is the situation today. My scientist friend Peter Williams agrees with the thrust of my submission  and agrees dirty pots are essentially the same with regard to plant health as putting new plants harmlessly into outdoor  soil.  He is adamant however that he will continue cleaning his pots although I don’t think he actually goes so far as washing them.

I am indebted to blogger Rick Nelson for alerting me to this myth. He empathised with me when I  previously described washing clay pots outside on a cold winter morning when I worked at Hartlepool Parks and Recreation Department. In those days pots were scrubbed to remove algae and lime. New pots were also soaked and washed to remove salts left from manufacture. Attitudes change, and I remember displaying Dicentra cucullaria in a large clay pot at the Harrogate Spring Flower Show. The dirty earthenware pot was covered with white lime and algal green. It was a star.

It is now fifty years since I washed a pot. I cannot remember even giving a pot or container as much as a light dry clean. Most, but not all, of my pots are plastic and have been reused numerous times. I do recommend  to gardeners to have a store of pots and sturdy seed trays to re-use several times rather than buying new fiddly flimsy containers and modules.
I had thought not cleaning my pots and seed trays was part of my slovenly nature. I am grateful to Rick for informing me that I am not unique.

Ammi was all over the place at a rather hyped flower show last year. I have succumbed to fashion.
Plant health is an essential part of plant management. There will be rare occasions when a dirty  plant pot harbours pests such as root aphid or root mealy bug. Heaven forbid, vine weevil larvae may lurk in some peaty compost. You might have even grown cabbages with clubroot . Perhaps your plants were dripping with red spider mite and some have gone into hibernation round the rim of your pot but I doubt it. In none of these events would I clean the pot. I would go further and throw them away.

You may be worried about the fungal fungus disease of seedlings called damping off when the contents of an infected seed-tray keels over and dies. This disease is associated with dirty conditions and unsterilised soil. I have unconventional views about this very important and ubiquitous disease.

We used to teach our students that damping-off was an infectious disease and not merely a disorder caused by bad management. We used to emphasise hygiene, clean pots, clean irrigation water, no drips from the glass and to always use sterile or sterilised compost. The principle was if you avoid the infection it will be impossible to get the disease. This is the conventional view. It is successfully achieved in commercial horticulture where potent chemical help is at hand.

For most of we ordinary gardeners the water carried spores of this disease are almost everywhere - albeit not in the air. In spite of this I think that the disease will not be a problem if we grow our plants well. I argue that It is impracticable to avoid infection by such things as washing pots, the disease will find another way in. The significant factor is that only If the plant is in a susceptible condition will it succumb to the disease.

Gardeners can do dreadful things to their plants. They sow them too early with excessive artificial heat when there is inadequate light to support them. Some even imagine that small plastic mini greenhouse-like structures standing on a shelf or only slightly better, on a  light windowsill in the house, are somehow suitable for seed-propagating plants. Gardeners are advised to cover their seedlings with a sheet of glass, all that humidity, no wonder they get drawn and keel over with rot!
The worst mischief is poor watering, This is a real problem because to the inexperienced gardener it is easy to go wrong. Knowing how much and how often to water is not always obvious. Too much water and high humidity are the conditions where damping-off thrives.

It is not always practicable for certain difficult plants but for all of the many plants I personally grow from seed the germinating seedlings are fully open to the air and I do not cover them. Very high humidity can be fatal. I thoroughly water at first sowing and for very small seed actually water the compost before scattering the seed. For other than very fine seed like antirrhinum I like the compost surface to get quite dry before I thoroughly water again. Damping off really does thrive when it is wet and humid. There will be some infrequent occasions where for very small seed a compost is dry at the surface and yet wet below. In these circumstances a light watering rather than a thorough soak may be in order but not every day!

Some gardeners do not realise that very thin layers of compost lie very wet after drainage and damping off may be more likely to occur.

There are two kinds of person when it comes to our own domestic hygiene. Some are constantly cleaning and every surface is regularly swabbed with some useless anti-bacterial product. Any food falling on the floor goes straight in the bin. Others amongst us are more cavalier and like to keep our immune systems primed. Some people wash pots and others don’t.

Healthy Corydalis lutea seedlings have ‘volunteered’ in my seed tray of recycled ‘compost’. I have now weeded them out and the germinating seedlings of Dictamnus fraxinella are now doing very well.


Superb dwarf Lilium formosanum pricei was sown six months ago in my unheated greenhouse. I will have hundreds of dwarf lilies flowering next year.

Sown two years ago, fresh seed of Fritillaria meleagris  germinated last February and were grown-on undisturbed in their tray. They are sprouting again. 
I have now patched them out on the village plot. The inevitable liverwort has not done any harm.


Addendum, do we have another myth?

Since penning this post six weeks ago I have agonised as to why our students when raising plants in college greenhouses for their plot projects almost always suffered from damping off! (The plants not the students). I have not personally seen the disease since I ‘retired’ from college more than twenty years ago and as this post makes clear my conventional plant hygiene is appalling! (I will however explain in a future post that in some aspects of plant hygiene how I am extremely strict). You will have gathered by now that not only do I not wash pots, I also recycle compost and soil!

I have now remembered that the students, who I hasten to add, were not under my charge, almost invariably covered their glasshouse sown seeds with polythene or glass. I have now seen the light and am certain that covering was the cause of their problem. Instructors ensured the students exerted the most extreme hygiene you could imagine yet the seedlings constantly keeled over.

Plants sown outside in the garden, either by the gardener or nature are almost never covered by anything but soil. You (normally) never get damping off outside. It suddenly dawns on me that covering glasshouse seed with plastic or glass is normal practice for many gardeners. I had somehow cut myself off from such technique and perhaps I have even regarded my own methods as rather more primitive. I now notice in magazines and gardening blogs people envelope seeds with plastic covers much of the time. How strange, I even spotted someone covering brassica seed with a glass sheet!

As is my wont to take things to extremes, for the last six weeks I have tried to get my uncovered seed and seedlings to succumb to damping off. I have watered some more often than normal, some with heavy drenches others with daily light trickles. As usual I frequently fail to find find my rose. Perforce they were unwatered for the five days when we were away. The only watering sin I could not bring myself to do was to leave my seed trays standing in water all day! 
Not a seedling has died and I have got healthy seedlings aplenty. 


Cathi came round last night and pointed out  that I was not a proper scientist and I did not even have the experimental control of actually covering any of my seed!  Shame on me but this would have been a bridge too far!

Saturday, 5 April 2014

How to grow Cyclamen coum


A mark of success is to have large drifts of Cyclamen coum all over the garden. On my sandy soil I fail, my own are fairly insipid. Quite galling really, when I pass my old garden at  Bolton Percy, fifteen years after my departure they are quite magnificent. Not my old plants but from their self-sown seed, the original plants were dug up a long time ago by a man with a spade. They are now to be found under hedges, in otherwise scruffy neglected corners and on the grass verge by the road. I wonder if the seed was taken there by the ants. I wrote about myrmecochory - I just love that word - in last year's post on Cyclamen hederifolium the easiest of all the hardy cyclamen to grow. 

I have some nice Cyclamen coum in my home gravel and rock gardens but they do not spread very well.

Although the ants have been busy
On the more loamy soil at my old home Cyclamen coum is very easy to grow and provides a lovely carpet of colour in early Spring. It has particularly thrived in this year’s warm February days. My friend Peter Williams made an interesting comment when he noted that you struggle for years to get drifts going and suddenly they reach a critical mass and you can’t stop them!

Cyclamen coum looked good in my old garden

It was struggling a bit in Bolton Percy churchyard
Collecting seed
I feel sorry for new gardeners who want to grow these lovely self-seeding cormacious plants. If you buy a packet of seed not only are they expensive you get very few seeds and not many germinate. Failing having a friend who grows them, the best way to build up your numbers eventually to hundreds is to buy a plant and save your own seed. Peter Williams whose fine plants I feature today, bought a rosy red one and a pale pink one at Anglesey Abbey National Trust nursery several years ago. He collected the seed, he got there before the ants and each plant gave him more than two hundred seeds. If not cross pollinated the seeds come fairly true. When eventually you become a  cyclamen connoisseur you will have so many seedlings  that you can start to become selective and save only the plants with the best foliage markings!

Get there before the ants. I always think of Zebedee in children's TV programmes when I see these coils unfurling many months after flowering 

Lovely foliage markings
You can select the best markings
The main secret of success  with seed is to sow them fresh. Best on the day you collect them.
The secret of failure is to buy dry corms. Always buy a plant that is growing! 

Success in a pot

Peter’s pots, home and away
I am particularly thrilled this year by the large pot of Cyclamen coum I feature. Guess who gave them to me last December! They have stood outside my conservatory and have been a mass of colour for more than three months. They are in Peter’s compost and all I have done to them other than watering is to give them a light top dressing of fertiliser in January. Absolutely magnificent and I now relish the prospect of collecting masses of seed. Peter tells me, much to my surprise, that each pot contains only six corms!

Peter has sent me some cultural information that I am passing on almost verbatim. Of course the Reading method  he describes is tongue in cheek. Who would go to that trouble or really believe that such precision is needed for success. Even Peter’s own method is too finicky for me. If seed fall to the ground and germinate as well as they do, they must be easy to grow. I used to propagate my (rather easier) Cyclamen hederifolium at my old home by sowing 200 or so seeds in a seed tray of multi-purpose peat based compost on the day I collected them in September. They germinated within six weeks and overwintered outside at the base of a sheltered wall (I had no greenhouse then). They looked so sad when frozen solid on a cold Winter’s morning! 

Peter’s Cyclamen hederifolium have sown themselves in his gravel road

Essentially my present method  of propagation is the same as Peter’s below. Without the frills I still get the thrills. Don’t let his commentary put you off because it sounds difficult. If you collect fresh seed and sow them straight away you cannot fail. I have to tell you that when I collect seed from Peter’s fine plants I will sow them in trays in a mixture of my garden soil and and composted green-bin waste given to me recently to keep me sweet, by the municipal composter who operates up the road. If I told you what goes into his green waste product you would question my sanity. From the ridiculous to the sublime you might prefer Peter’s middle way!

Peter Williams' notes on propagating Cyclamen coum

Germination: difficulties expressed by members of Cyclamen Society – They refer to the Reading System. Quote from website “Members write to the Journal more often about seed sowing success and failure than about any other topic. Many of the contributions below describe the experiences of Society members in the light of the University of Reading's work for the Society on seed germination. As reported in the Journal (June 1993, p2), this "Reading method" showed that for at least C. hederifolium and C. graecum success depends on complete absence of light for 15 to 26 days, a temperature of 15°C (59°F) and certainly no higher than 20°C (68°F), and a constant supply of moisture without flooding, drying out, or even minor fluctuations.”

Peter's system – Fresh seed – sow immediately the seed pods split open – June,July/August/Sept depending on which species I am growing
Compost: 80% fine peat:20% horticultural sand.  To the peat component I add 2g per litre of dolomitic limestone and to the whole compost (peat + sand)  I add 1.5g per litre of micro granule slow release fertiliser  6-9 month release.
I usually make a batch of the peat/sand + chalk base mixture and then take out say 1 litre and add the slow release fertiliser when I need it.  The base mixture keeps indefinitely. I use a plastic measuring jug to measure the volume of compost and on electronic kitchen scales (most will weigh as little as 1-2 g) to weigh the chalk and fertiliser.
If I store the seed over winter I rehydrate by soaking in tap water for 24 hours before sowing. I do not wash fresh seed but many growers do to remove the sticky ant attractant. (no danger of ants pinching the seed that way!)
I sow the seeds and cover with a few mm of compost and then a few mm of alpine grit.
The seeds will germinate equally well in a slightly heated propagator (at 10-20C) or in a cold glasshouse (or outside) but they germinate somewhat faster in the propagator. Germination  occurs 3-6 weeks after sowing.
I leave the seedlings in the seed trays for the whole of the first year and occasionally give them a feed with tomato food. They are not pricked out. The seedlings become dormant over the summer and I repot into individual pots in August – essentially after 1 years growth.
Potting compost for the older plants is 3 parts peat or recycled compost – any that I have : 2 leafmould : 1 alpine grit. I rarely use new peat but if I do I add 2.0 g dolomitic limestone per litre of peat.  To the whole compost I add 3g litre of 12-14 month slow release fertiliser.  Again I make up a large batch of the base compost and only add the slow release fertiliser just before I use it. 
A few plants flower in their second growing season and all within 3 years.  
Seed sowing in Peter’s greenhouse trays
One year after sowing. Soil scraped away to show corms ready for potting
Commentary on flexibility of horticultural method
I am immensely grateful to Peter for his valuable and precise information. It is specially valuable to those who like to make their own compost - and lets face it there is an awful lot of commercial rubbish around. I make my own compost too, but I use my own garden soil and measure ingredients in dollops and slack-hands-full rather than with precision. I have commented before that the difference between John Innes 1 and 2 is 100% in strength and yet it is often a marginal decision which to use and one partly dictated by likely subsequent management. Peter shows his own flexibility too when he mentions reusing the cyclamen seed compost when he makes up his stronger potting compost in the second year. Who knows, growth of beneficial mycorrhiza might have got underway! Peter’s mixes are precise but I am certain that if a current mix is suitable for a different plant he will use it.
If a plant such as cyclamen sows itself in the ground so readily it must be easy and the methods of growing are legion. I have often pricked or patched out self sown seedlings and potted then up for friends at any time of the year. Strictures against dry corms are about those out of the packet, not those from the soil. Soil-to-soil movement of plants is much more successful. When I used to have seed trays of hundreds of crowded corms one year on from seed - like in Peter’s picture - I would sow them like peas on my vegetable garden to grow on for their second year.
Peter also has a wonderful display of different species-cyclamen in his cold greenhouse.


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