Phragmipedium kovachii Culture Notes

I attended Peter Croezen's presentation on this amazing plant last week and the following is what I learned.

Light
Seedlings must have low light at 400-450 footcandles. Higher light will cause fatal leaf yellowing.

Water
Use pure water (such as distilled, rain or RO). Keep moist but not soggy. They really like growing their roots into water; using PrimeAgra creates an environment that keeps the roots very moist but not too soggy.

Fertilizer
Use a mineral-rich fertilizer at 200ppm every week. Calcium, magnesium and boron are important.

Temperature
Keep a relatively constant temp. of 20C. Higher temps (above 24C) will cause fatal leaf yellowing.

Media
As newly deflasked seedlings, pot into a small 2" container, in sphagnum moss, and keep moist. When a considerable rootball is developed, pot up, into PrimeAgra or bark.

I have ordered a Pk seedling from Mr. Croezen.

Planting Cypripediums, Volume 3

In this third and final volume I'd like to discuss care after planting, on a seasonal basis.

Spring

In the spring Cyps will emerge from the ground after the dormant period and almost immediately begin flowering. Remove any mulch after last frost. It takes about 2 weeks to completely unravel the leaves and open the flowers. The flowers will last for another 2-3 weeks. Different Cyps have slightly different times at which they emerge and flower, and different rates at which they grow. At this time you want to fertilize lightly, using half strength orchid food every two weeks or so. Remember not to let the soil dry out completely, with the exception of C. acaule, which only ever needs to be watered in drought years (unless you need to adjust the pH with vinegar solution). If you want cut flowers, cut as short as possible and only on large established clumps; it weakens the plant.

Summer

After flowering, Cyps enter their active growth phase. You can't tell from above ground, but underground the plant is producing new roots and next year's growth buds. During this time they need the most fertilizer (especially hybrids and reginae). For hybrids and reginae, use Miracle-Gro or comparable product as for perennials; for all others use the half strength orchid food every week. It is also advisable at this time to mulch with organic content; this enriches the soil and keeps it cool and moist (don't do this for C. acaule and NEVER fertilize it! Mulch with conifer needles instaed).

Fall

As the weather changes the Cyps will begin to enter their dormant phase. The leaves will turn yellow, then brown (some just turn brown). Once the growths are completely dead, you may remove them if desired. If you are lucky you may have some seed pods on flowered growths; if so you can either leave them to disperse the seeds naturally, or spread the seeds over the ground yourself. Perhaps one day I'll create a post explaining how to sow seeds in the lab... doing it the natural way will get you flowering plants in 10-16 years if you're lucky. Now mulch with a few inches of dead leaves for winter protection.

Winter

During the winter Cyps have their dormant period. If you're growing in containers, keep the plant in the crisper drawer of a fridge for at least 3 months, BARELY damp.

Happy growing; this concludes Planting Cypripediums!

Planting Cypripediums: Volume 2

This second of three volumes is on soil mixes and hardiness for individual species and hybrids.

The most common Cyp. species are C. acaule, C. calceolus, C. formosanum, C. kentuckiense, C. macranthos, C. montanum, C. parviflorum, C. reginae, and C. tibeticum. The most common hybrids are C. Aki, C. Emil, C. Gisela, C. Hank Small, C. Inge, C. Ingrid, C. Maria, C. Michael, C. Philip, and C. Ulla Silkens. Hybrids grow pretty much the same; species have individual needs.

C. acaule requires a very acidic soil, pH 3.5-5. I recommend spreading the roots over sand and covering in pine mulch, then watering sparingly with a solution of pure water and vinegar, at a rate of 1 ounce vinegar per gallon water. Hardy to zone 2.

C. calceolus should not be confused with our native yellow lady's slipper (C. parviflorum). I am referring to the European clone. A pH of 7-8 is necessary, with perfectly-drained soil. Use a balanced mix with loam, sand and gravel. Hardy to zone 3.

C. formosanum makes a great potted plant if it isn't hardy to your region. Known as an easy species, it prefers a pH of 6-7, in a well-drained soil. Always add drainage material in the bottom in the pot. Hardy to zone 6.

C. kentuckiense is just beginning to gain popularity. It is sought-after for its large flowers (largest in the genus). It likes a sandy soil with a pH of 5-6. I recommend using mostly sand with a little loam and a top-dressing of conifer mulch. Hardy to zone 3.

C. macranthos is very popular for its showy flowers in shades of pink, purple and red. It must have a prefectly-drained soil; use a well-balanced mix with loam, sand and gravel; pH around 7. Hardy to zone 2.

C. montanum is sought-after by collectors but has a reputation of being difficult to grow. It must have a sharply drained soil with plenty of gravel and sand, pH 7-8. I recommend planting on a slope. Hardy to zone 2.

C. parviflorum is the most common Cyp. It is easy to grow in a well-drained soil, pH 6-7. Hardy to zone 2.

C. reginae is the most majestic of the Cyps and is highly sought-after. It is relatively easy to grow in a well-drained soil, pH 7-8. Likes lots of moisture (NEVER wet!) and fertilizer. Hardy to zone 3.

C. tibeticum is a collector's species that is closely allied to C. macranthos but has darker maroon flowers. It requires perfect drainage, pH around 7. I'm unsure about hardiness but it has been grown in zone 3.

All hybrids like well-drained soil and lots of fertilizer, pH around 7. They're all hardy to at least zone 3.

The third and final volume will be about care after planting.