When I talk to people about orchid care, there is this idea that there is an “orchid rule book” and it drives me bonkers. I get how “rules” can in-theory be helpful for new growers. However, the problem comes when the rulebook is full of false facts (because conditions and care will vary depending on your climate). People look to the culture sheets by the AOS and/or other resources and take them as gospel, but they likely don’t understand the relationship between humidity and evaporation and assume the care sheet was written with their conditions in mind. The number of times I’ve had people tell me, “you’re doing it wrong” is hilarious…meanwhile, my orchids look better than most greenhouse-grown plants. With this in mind, I’ve decided to start a series of “breaking the rules” where I take an orchid culture sheet on a specific genera and I red line it and explain why the culture sheet is either misleading or wrong. Where possible, I’ll amend it so it’s more accurate.
With the intro out of the way, let’s get started with an easy one:
Phal Culture According to the Canadian Orchid Congress Care Sheets
Moth orchids are the most popular orchids and are very easy to grow
in most homes with high humidity being the most difficult growing requirement to meet. because of their tolerance to a wide range of conditions and ability to grow even when humidity is less ideal. You see, while high-humidity makes orchid care easier, if your home is dry, there are many ways to successfully keep phals without having to modify your home environment.
Popular images of the phal include: Flat, glossy, spreading leaves support arching spikes of large white, pink, striped or yellow flowers; or smaller flowered varieties with greater numbers of flowers (multifloral), or varieties with brighter colors and fewer flowers (novelty) are also popular. Beware: there are a few different types of moth orchids; some are warm-blooming species that come from hot and humid rainforests near the equator (these have a tenancy to produce ever-blooming spikes that should only be cut after they turn brown) while others, the more common type, come from higher elevation (slightly further north from the equator) and are better-adapted to manage dryer climates and seasonal changes (temperature swings between 14-28C). No matter which type of Phalaenopsis you keep, your potting mix, watering tempo, and the care you provide the plants can allow you to grow all types of phalaenopsis in your home environment with success.
Healthy Phalaenopsis start with healthy roots:
- Potting Mix: Pot in a coarse bark medium.
Beginners shouldAvoid moss only and soil only basedmixes as they have a tendency to sop up too much water and cause issues with the roots simply because they remain too wet for too long. Adding a small amount of sphagnum moss or peat moss to your bark mix can help slow the drying rate, and many growers have success, simply lining a thin layer of sphagnum moss on top of the orchid bark. Fir bark mixtures are bestideal because bark absorbs water and over time as the water evaporates, it keeps the humidity around the roots high with 1.5 to 2.5 cm chunks of bark.
- Repotting: Repot when medium starts to decompose. Check yearly, on newly purchased plants or if leaves are limp. Always repot new phals – you’ll have better control your care if you know the potting mix works well with your watering process and schedule. If your orchid starts to slow growth after 8-16 months, it’s time to repot as this likely means the media has began to decompose.
- When to Repot: Remove old medium if it is loose and any rotting roots; choose a plastic pot that will only just hold the roots of the plant and center plant in new pot. The bigger the pot, the slower the media will dry – your goal is to have the media approaching dryness after about 5 days, but before 10 days; having a pot that’s too large for the amount of roots (called “overpotting”), may lead to issues because the media stays moist for too long; however if your plants are drying too fast, slightly overpotting can allow you to water less frequently. If it takes the pot longer than 7 days to dry, you should consider a smaller pot or use a larger chunk bark mix.
- Air Roots: Phalaenopsis may grow roots over the side of the pot and up into the air. Leave these roots on the plant, perhaps misting them when the plant is watered—if you’re misting, soak the roots so that they turn an even green, if they are patchy green, wait 5 minutes and spray again.
- When to Water: Roots in the potting mix should be moist at all times. Water when medium has begun to dry but is still damp. You may notice the upper roots and surface of the potting mix dry faster than the inner section of the potting mix—that’s okay, your goal is to water as the inner area of the pot is approaching dryness; if the bark inside the pot is bone dry, water now. A good sign of when to water is when the roots in the pot start to silver; if the air-roots (roots above the top of the pot) are getting wrinkly (like a raisin), your plant is dehydrated and you should water liberally. Brief soaks work well to hydrate a plant and roots, but avoid letting a pot soak in water for more than 15 minutes; if you accidentally forget and it soaks overnight, it’s not going to kill the plant, but to avoid rot issues, it’s best to keep the soaking to short intervals.
Water thoroughly, particularly if your water has a high mineral content.
- Water Quality: Do not use water softened in salt-consuming water softeners – it’s high in sodium and can lead to growth issues because sodium dehydrates the plant.
Low mineral water is preferred, such as naturally soft water or rain water.If hard water is used, water very heavily to flush minerals. Flushing your pots with ample water is ideal; this is referred to as “leaching” and it ensures old minerals redissolve are removed from the pot; this keeps your potting mix ideal. Note: fertilize AFTER you leach/rinse the pot a few times and Use room temperature or warmer water. Avoid leaving water standing in the crown of the plant as this causes fatal rot.
- Foliar Feeding & Wet Leaves: Phals can absorb nutrients and water through their leaves; when watering it’s good to drench the plant, leaves and all. Some growers may experience issues with “crown rot”, but this is a sign that humidity is too high and/or the plant has a Calcium deficiency. Supplement with CalMag if crown rot is an issue, and increase air circulation with a small fan to your growing area. It is best to ensure water on the leaves is dry within 4-6 hours – blowing out or dabbing residual water with paper towel works well.
- Fertilizing: Fertilize weakly and frequently with a balanced fertilizer. One-eighth to one quarter strength recommended by manufacturer for house plants every week in spring and summer and every two weeks in autumn and winter. Organic fertilizers such as blood meal and other “slow release” fertilizers can be used, but only add ~ 1/8-1/4 tsp per pot.
- pH: Phalaneopsis are epiphytes which means in nature they grow on trees and are watered by rain water. Rain water has a pH of 5.6 and at that pH nutrients have a specific solubility. If you have alkaline or very acidic water, consider pH-adjusting for better growth results. It’s not a requirement, but you can achieve better growth and flowering if your pH is dialed in.
Healthy leaves produce more and bigger flowers:
- Low light levels
are appropriatewill keep a plant alive; however, if you want a phal to grow and do well, you should provide closer to intermediate light. Leaves should be a medium green, not yellowish or dark green. They should be firm, not long and floppy (more light needed). A dark red blush covering the top of the leaves means too much light.
- Ideally you want 8-14 hours of good light for best growth. This may mean a few hours of direct early morning or evening sunshine followed by a day of indirect light near a large window, or using artificial lights (LEDs/florescent).
One to two hours of sunshine on a windowsill (East recommended) or 15-30 cm under a two tube fluorescent fixture.
- Leaves should be firm; if soft, wrinkly or
anddesiccated, check roots for rot, and repot if necessary. If the roots are fine, ensure you’re watering as the media approaches dryness. High humidity (such as enclosing the plant in a plastic bag) will aid recovery if most or all of roots lost, but be careful ofrot is more likely to happen if you enclose them in a bag like this.
- Phalaenopsis do best with
60-70%50-65% humidity, but will grow and bloom , although more slowly and with fewer and smaller flowers,in lower humidity. You can use a Usehumidifier to raise humidity; however, regular watering and a good routine can be more effective than trying to alter your entire home environment – humidity pans and misting rarely effective.
Enclosing plant growing areas
is effective but ensure fresh air and air movement to avoid mold and rot. can be effective, but may also present issues of rot and mold if air circulation is poor.
- Grow Phalaenopsis in warm temperatures with 18°C minimum winter nights (except if forcing flowering) and 32°C summer day maximum. Ensure 6-12°C day/night difference to aid flower formation.
usually will bloom annually under ideal conditions. The flowers last for several weeks if the plant is being cared for properly and there are no sudden shifts in temperature or humidity:
- Maintain plant orientation while spike is growing for best display; the flower spikes grow toward the light and changing the angle of the plant to the sun will result in the spikes making S like shapes as they follow the changing angles.
- Buds turning yellow, wilting and falling prior to opening is from not enough energy in the plant to open the flower either because the light is too dim, the plant is too small, or the roots have rotted. Also caused by ethylene gas (produced by ripening fruit), or too great a temperature variation.
- On healthy plant, a second set of flowers may result if spike cut back to one of the non-flowering nodes on the flower stem after the first flowers fall. Do not try this if the plant is not healthy and growing new roots and leaves.
- If healthy, mature plant fails to bloom, provide slightly brighter light and lower night temperatures (14°C nights) for the month of October.
- If leaves start to wilt while the plant is blooming (or at any other time), cut off the flower stem at the base, and check for broken down potting medium and rotting roots.