Cypripedium growing media

[evolutionplantsman]

I'm new to the forum, at least as a contributor, but was prompted to post this question by another member, who thought that this would be the best place to ask about Cypripedium cultivation.

By way of a brief background, I have ordered a small number of tissue cultured Cypripedium from Plantek, a tissue culture lab in Canada. They are due to arrive early next month. I had planned to put them in pots in my normal growing medium and then, presumably, mourn their departure from this world as they gradually declined and succumbed to various ailments under my 'care'. However, I gather that expert Cypripedium growers use a growing medium based on cat litter (it is even said that Tesco makes the best) with great success. Perhaps, with some guidance, I might aspire to keep the plants alive for a while...

My questions are:

1. Is there a consensus recipe for the ideal Cypripedium growing mix and, if so, what is it?
2. Given that my plants will arrive as little, dormant fragments of tissue, where should I keep them over winter? The options are a frost-free polytunnel, an unheated shade tunnel or outdoors.

I live in Wiltshire - wet, windy and allegedly mild, although last winter, as everywhere, it got quite cold.

Any suggestions would be very gratefully received. It would be impossible to assume too much ignorance on my part.

Tom (Mitchell)

[Maggi Young]

welcome, Tom,
 good to have you posting.
David raised your question with us..... see here: http://www.srgc.org.uk/smf/index.php?topic=4294.0     

[Stephen Vella]

Tom

There are many reciepes for Adult Cyps out there but remember that it must be free drained. Quartz sands, grit, perlite, seramis, coco fibre, decomposed bark etc. Repot every 3/4 years.

Before potting up your seedlings make sure you wash off all the agar as this will encourage rot.

Plant in plastic squat pots.

For seedlings best mix for me was equal parts of sand and perlite, make sure you sterlise the sand. Stay away from any organics at this stage it will only encourage pythium rot as I found out. I tried using 10% coco fibre as suggested, good for some but not for others.

Make sure you plant them so the bud is just below the surface and I use grit to top it off, stops the perite from blowing away. If you have seramis use instead of perlite. I have never tried using cat litter, must try it one day.

Keep your seedlings in a cold frame in the shade all of winter or your polly tunnel but be sure its 5c and below for 3 months at least. Sink the pots in sand also, prevents tempreture fluctuations and keeps it cool. Shelter from rain and hand water so you kow how much water they are getting, so water every 2/3 weeks and be sure to keep them just moist, this is important during their first winter. You may find some deaths in this first year, depending on what you grow, most of frosch hybrids are hardy, reginae, californicum and macranthos, kentuckiensis are the easiest and some Asian ones are just difficult. 

Use an inorganic fertiliser when buds start to appear in early spring. 1/10 strength in the first year every 2nd or 3rd week and be sure to water between fertilising.

hope this helps

[mark smyth]

Tom, do you know there is a tissue culture lab in Belgium? I'll look up their details for you

[evolutionplantsman]

Wow - many thanks! All advice taken on board. In return, I'll report back to the forum in due course on my success or otherwise. If I can't get them to thrive now I shall go back to growing lettuce.

[Ragged Robin]

Tom, welcome to this great Forum, a gold mine of information    Questions like yours open another avenue to explore with you at the sharp end  

[David Nicholson]

Welcome Tom, glad you decided to join in with us, and there is probably more advice to come.

[Slug Killer]

This lab in Germany is also very good and cheap for hybrids. Better to learn mistakes with cheaper plants than expensive ones.

I found my seedlings from here were bigger than anywhere else I ordered from.

http://www.in-vitro-quedlinburg.de/eng/in-vitro-plant-gb.html

Regards

David

[Slug Killer]

You may also find these useful.

http://www.srgc.org.uk/wisley/2008/100908/log.html

http://www.srgc.org.uk/wisley/2008/280808/log.html

Regards

David

[evolutionplantsman]

Thanks again for the tips and for the warm welcome to the forum.

I have a couple of supplementary questions after reflecting on the excellent advice so far.

1. I'm often puzzled by instructions to keep plants below a certain temperature for long periods because, without the co-operation of the weather, I don't see how it can be done. On a small scale I guess one could put pots of Cypripedium in a fridge over winter (has anyone tried this?) but I will have far too many plants for this to be practical. I hear the suggestion about sinking pots in sand, which I shall try, but I still think temperatures will inevitably be above 5 degrees C for much of the winter. Any further suggestions?

2. Regarding organic matter in potting mixes, are fungal problems a result of using non-sterile organic material or do the spores arrive after potting? I have had great success with herbaceous perennials using a heat sterilised coir-based potting mix (in direct comparisons with peat it results in considerably better root growth) and few problems with fungus but then, I cheat and use commercial fungicides.

Tom

[LarsB]

I grow my seedlings outdoors, except for californicum sa it doesn't really like frost. When i receive them in the autunm i plant them in a non organic mix. I'v etried mixes of sand, perlite and cat litter, sand and perlite, and pure catlitter. I haven't noticed any significant difference. I the beginning i tried mixes with organic matter and that was defiantely not a good idea. The climate here ensures that they get the cold treatment they need. We havent' had serious frost i nthe four years I've experiemted with Cyp seedligns, which means that we havent' been below -10 degrees celsius.

[Stephen Vella]

Tom it would help to let us know where in the world are you and what climatic zone you are in. This will help with what sp you can grow??

What are your winter highs and lows and summer temps highs and lows in the shade?


When talking organics matter for Cyps they really do love it when they are cultivated in the ground. When in pots its a whole differant story. The organics incourage a build up of bacteria/fungus that break down the organic matter too fast and can release too much nutrients especially if you are cultivating in a warm climate also its been found that these bacteria and fungi can attack the cyp roots and slowly killing the Cyp. When in their 3rd year you may get by adding 10% decomposed bark as theres little nutrients here but the mix needs to be change every 3 or 4 years if you are using it. And its good practice to do this as to see how the Cyp roots are developing and if its going backwards take the bark out of the mix. It may sound crazy but Cyp seedlings can do with out it.

C reginae, californicum, parviflorum, formosanum and macranthos are easy sp to grow and all of Frochs hybrids are easy as well and recomend. The Asain sp are mostly hard to cultivate as its been found that they really dont like organics and like to be kept on the dry side in winter and i killed a lot in learning.

You may need to water every second day when its dry summer.

Be warned its very slow to flowering when growing Cyp seedling from flasks and you maybe better off purchasing 3 year old seedling instead of deflasking seedlings as somebody else has done all the hard work as to weaning them onto a potting medium but if your keen go for it.

cheers

[Jeff Hutchings]

Hi Tom,

Without wishing to step on toes, the last thing I would do is recommend that someone new to cypripediums starts with seedlings. It is much better to buy in 2/3 year in compost plants and grow them on than watch seedling die off. I get numerous calls and emails from people who have bought seedlings or young plants. This year cypripediums were being sold 3 in a pot in 5 cm pots and the buyers were finding it difficult to keep the plants alive, even whilst they sought advice!

Something that bugs me is the term tissue culture when all the cypripediums are grown from seed but that is a side issue.

What your seedlings need is vernalisation in the fridge for the winter. I have problems up here in Lancashire with seedlings kept in the polytunnel as they do not get enough cold for the 12 vital weeks and are then reluctant to develop leaves so into the fridge they go. Mine usually arrive de-flasked though and I keep them in the plastic containers they arrive in.

I would not plant them until the spring, then into a fishbox with a high inorganic mix (personnaly I do not like seramis and have never had much success with it). By using a big container you do not get the rapid drying out that occurs in an individual pot. Provided I space the plants out I do not get problems if any die. They can stay in this container for at least two seasons. The insulation properties of the box also helps keep it cool during the summer period. I find it is the early summer when problems arise, especially if the temperature goes up quickly. They need cool shelter. The shelter helps to stop the surface drying out too quickly. If the compost is very open then the plants can be watered very regularly. This reduces the temperature and plant stress.

Good luck with the seedlings.

Jeff