Cultivation - cypripedium

SUMMARY
Cypripediums can be planted out in the garden (shown in black) or grown in pots (shown in blue).

These instructions are very general and suit most cypripediums which are readily available. However, it is recommended that you ask for a culture leaflet when purchasing a plant, because the rarer ones have very specific requirements regarding soil type, pH etc. 

DETAILED INSTRUCTIONS

TEMPERATURE
All Cypripediums are hardy. Frost protection is not necessary. However, Cyp. formosanum is one of the earliest flowering and has rather delicate flowers, which benefit from a little protection.

LIGHT
Cypripediums enjoy good light, but must be shaded from strong sun. Plant them in a position that gets sun in the morning or afternoon but none at midday. The north side of a tree or bush is ideal.

In pots: north, east or west facing

WATERING
Cypripediums must never dry out, but should not be allowed to be water logged. Therefore add a liberal amount of gravel (50%) to the planting site to aid drainage.

In pots: water liberally when growing but during dormancy protect from rain and keep just moist.

FEEDING
Cypripediums are moderate feeders and all fertilisers should be diluted to about 1/4 strength of that indicated on the pack. I use a liquid fertiliser throughout, switching between Seaweed Extract and Fish Emulsion at every other watering.

RE-POTTING
Re-potting should be done after flowering in the autumn. 

Pots and Containers
Cypripediums need a good root run to develop strong shoots for next year. A 2 litre pot is a minimum, most adult cypripediums should be grown in 5 litre pots. Fill the pot 1/3 with compost, making a cone shaped hill in the pot. Gently arrange the cypripedium roots on top of the 'hill' and fill with compost all round. Do not firm in. The top of the shoot should be 2 inches (5cm) below the soil surface. Tap the pot on the ground to settle the compost and fill in more until the shoot is just covered. Then finish off with a layer of grit, pumice (if you can get it), Seramis or well rotted pine needles.

Tip: Use pots that have two tier or side drainage. Bowls that have holes just in the bottom should be stood on gravel, pebbles, Hortag or similar so that water can drain away easily. Never allow cypripediums to get water-logged or the roots will rot and the plant will perish.

Compost
The compost mix should provide good drainage yet retain sufficient moisture for the plants to thrive. This can be achieved in many different ways, using a variety of components. In essence, compost for cypripediums should contain slightly more drainage material than organic material.

A simple compost for cypripediums consists of half and half:

• organic content such as a loose mixture of fine bark, sieved oak or beech leaf mould, rotting pine needles and perhaps some fibrous loam, 
• inorganic content for drainage such as coarse grit (3 - 7mm), perhaps incorporating some pumice or super coarse perlite, well washed.

Notes on over-wintering: it is essential that the plants are well drained but not dry during this period. Therefore, if you grow your cypripediums in pots in a cold frame leave the lights on to keep out excess rain, but leave them slightly open to allow air circulation. You may need to water them occasionally to stop the compost from drying out.

PESTS
Cypripediums need protection from slugs and snails when the new shoots emerge in spring. Vigilance is required here, or your treasured plant will be gone before it gets a chance.

PROPAGATION
Cypripediums can be divided by splitting the dormant rhizomes, leaving one or more shoots per division. It is recommended to split clumps when they reach 20 or so shoots, or the clump may collapse and perish. The reasons for this are not well understood but, using a precautionary principle, better safe than sorry.

Make sure you label them - it's so easy to forget...

HOME