Lady slipper orchids, also known by their scientific name Cypripedium, are striking, unique flowering plants that are highly sought after by orchid enthusiasts and collectors. With large, pouch-shaped blooms in colors ranging from white to yellow to pink and purple, lady slippers stand out with their unusual floral structures. They require particular growing conditions and care to thrive, but their exquisite blooms make the effort worthwhile. This guide will provide tips and instructions for successfully cultivating lady slipper orchids at home.
Selecting the Right Lady Slipper Species and Hybrid
With over 50 different lady slipper orchid species, it’s important to select the variety that will do best in your climate and growing conditions. Consider the following when choosing plants:
- Climate – Lady slippers originate in temperate regions of the Northern Hemisphere. Choose species native to climates similar to yours. Tropical lady slippers won’t fare well in cold winters.
- Growing conditions – Factor in light, space, and soil needs. Some require abundant sunshine while others prefer shade. Ensure you can provide suitable habitat.
- Plant size – Lady slippers range from 6 inches to over 3 feet in height when mature. Select plants appropriate for your space.
- Blooming season – Most lady slippers bloom in spring, but some summer-blooming varieties are available. Choose plants that complement your landscape’s peak flowering times.
- Hybrids – These cultivars merge desirable qualities from different lady slipper species. Consider robust hybrids for easier growing.
Popular lady slipper species and hybrids include:
- Cypripedium reginae (Showy lady’s slipper) – Pink and white blooms on plants reaching 20 inches tall.
- Cypripedium parviflorum (Yellow lady’s slipper) – Yellow flowers on shorter 8-15 inch tall plants.
- Cypripedium acaule (Pink lady’s slipper) – Vibrant pink blooms on 6-15 inch plants preferring shade.
- Cypripedium ‘Gisela’ – Vigorous hybrid with large white flowers marked purple and yellow.
Growing Conditions
While thriving in the right habitat, lady slipper orchids require specific environmental conditions to flourish:
Light
- Most prefer bright indirect or dappled sunlight. Provide a few hours of sun filtered through trees or use sheer curtains.
- Avoid hot direct midday sun which can burn leaves. Morning sun or afternoon shade creates an ideal light level.
- Low light slows growth and reduces blooms. If sunlight is scarce, consider supplemental lighting.
Soil
- Lady slippers need acidic soil with a pH between 5.5-6.5. Test and amend soil as needed.
- A loose, airy growing medium such as coarsely grated fir bark keeps soil from compacting.
- Areas with alkaline soil may necessitate growing lady slippers in containers with customized potting mix.
Moisture
- A consistently moist but well-draining soil environment is critical, as both excessive wetness and droughts can kill plants.
- Use pots with drainage holes, avoid waterlogged sites, and water thoroughly without saturation.
- Add organic matter like compost or peat moss to help the soil retain some moisture.
- Humidity trays or regular misting provide added moisture to parched air.
Temperature
- Ideal temperatures are 65-75°F during the day and around 60°F at night.
- Most lady slippers require a winter dormancy period with cooler 50-60°F temperatures.
- Move potted plants to an unheated garage or cellar for winter dormancy if needed.
Propagating Lady Slipper Orchids
Lady slippers can be propagated by seed or through division of mature plants. Each has its challenges:
Propagation by seed is difficult and extremely slow. Fresh seed has a short viability window and requires a sterile growing medium containing the right fungi to germinate. It can take over 5 years for seedlings to bloom. This propagation method is not practical for home growers.
Division of mature, multiple-stemmed plants is a more feasible approach:
- Identify a stem growing from the rhizome that can be separated.
- Use a sterile, sharp knife to cut apart plants, ensuring each division has 3-5 growth buds and healthy roots.
- Replant divisions outdoors in early spring allowing time for root establishment before summer.
- Keep divisions humid, shaded and cool until new roots generate and growth resumes.
- Dividing large clumps every 3-5 years in spring invigorates plants and prevents overcrowding.
Planting Lady Slipper Orchids
When adding lady slipper orchids to your garden or landscape, observe the following guidelines for success:
Location – Select a suitable spot with bright dappled or indirect light and acidic, fast-draining soil. Avoid areas where water collects.
Site preparation – Test and amend soil pH and drainage as needed. Remove weeds, debris and competing plants.
Planting time – Transplant lady slippers in early spring after the last frost but before new growth begins.
Planting process – Dig holes 2-3 times the width of the root mass, positioning plants at the same level they grew previously. Spread roots horizontally and fill holes firmly but avoid compacting soil. Water thoroughly.
Companion plants – Group lady slippers with other acid-loving plants like rhododendrons, camellias, and azaleas.
Mulching – Apply 2-4 inches of pine bark, needle duff or similar mulch to conserve moisture and moderate soil temperature. Leave space around plant crowns.
Caring for Potted Lady Slippers
Growing lady slippers in containers allows more control over soil, moisture, and winter dormancy needs. Use these tips for successful pot culture:
- Select a pot only slightly wider than the plant, with drainage holes. Plastic pots retain moisture better than porous terra cotta.
- Use an orchid growing medium or create a well-aerated mix containing compost, peat, and perlite.
- Place pots atop humidity trays lined with pebbles and water. Generate humidity with misting or gravel evaporative cooling systems.
- situate potted orchids where they’ll receive maximum indirect or dappled light. Rotate periodically to discourage uneven growth.
- Water thoroughly then allow pots to nearly dry out before watering again. Orchids prefer constant moisture but dislike soggy roots.
- Feed weekly with dilute orchid fertilizer during spring and summer growing season. Discontinue in fall.
- Move potted orchids to a cool basement or unheated porch around 50°F for a 2-3 month winter rest period.
Troubleshooting Common Lady Slipper Problems
Monitor plants closely and act promptly if issues arise:
- Slow growth and small flowers indicate insufficient light. Move plants or trim overhead branches.
- Yellowing leaves signal overwatering. Allow soil to dry before watering again. Improve drainage if needed.
- Brown leaf tips or curled leaves show low humidity. Increase watering, misting and air circulation.
- Failure to bloom can arise from inadequate winter dormancy or dividing/transplanting at the wrong time.
- Pests like aphids, spider mites and mealybugs can infest plants. Isolate and apply horticultural oils or insecticidal soap sprays.
- Fungal diseases are common during periods of excessive moisture. Space plants for air flow and promptly remove affected foliage.
Frequently Asked Questions About Growing Lady Slipper Orchids
Get answers to some common queries about cultivating these exquisite flowering plants:
Do lady slipper orchids rebloom every year?
Yes, healthy lady slipper orchids typically rebloom annually when provided with suitable growing conditions and adequate dormancy. Old or damaged growth should be clipped off after flowering finishes to encourage new blooms.
What USDA zones can lady slippers be grown in?
Most lady slipper species thrive in USDA zones 3-7. Select cold-hardy varieties for colder regions and choose more heat-tolerant types for southern zones. Check species hardiness when choosing plants.
Should I cut back lady slipper foliage after flowering?
No, leave all healthy green foliage intact after blooms fade. Next year’s flower buds will form on this season’s growth. Only remove spent flower stems and damaged leaves that turn brown.
How long do lady slipper orchids live?
Given proper habitat, lady slippers can live for over 20 years. Mature, undisturbed clumps spread to form large colonies. Dividing plants periodically rejuvenates growth and avoids overcrowding.
Can I grow lady slipper orchids indoors as houseplants?
Growing lady slippers as houseplants is challenging but can be done by carefully replicating the conditions they need, like humidity trays, grow lights, and winter chilling. Outdoor culture is easier and more successful for most homeowners.
Do deer eat lady slipper orchids?
Deer avoid these plants, making lady slippers useful additions to gardens prone to deer browsing. Their thick rhizomes also deter damage from burrowing pests like gophers. Protect young plants with wire mesh until established.
Propagating, Planting, and Caring for Magnificent Lady Slipper Orchids
With striking, pouched blooms in an array of captivating hues, lady slipper orchids are prized additions to woodland gardens and natural landscapes. By selecting suitable species for your climate, providing appropriate growing conditions, and following proper planting and care techniques, you can successfully incorporate Cypripedium lady slippers into your garden. These lovely yet particular flowering plants will reward careful cultivation with their unique ornamental flair for many years to come. With the helpful growing instructions outlined here, you’ll be on your way to mastering the nuances of cultivating these botanical beauties.