Moth Orchids(Phalaenopsis) And How to Grow Them

WATER Moth orchids need to be kept moist since they have no pseudobulbs to store water. Allow them to dry out slightly before watering again. Never lat phals get bone-dry. As with all orchids, water plants thoroughly early in the day, so that the leaves are dry by nightfall. It is especially important not to let water sit in the crown of the plant (where the leaves emerge) as phalaenopsis are susceptible to crown rot. Filtered tap water, or rain water, is best. Water should be tepid, not cold, i.e. above 60 degrees. Watering schedules will vary considerably depending on light and temperature conditions. Plants may dry out rapidly in warm dry conditions, needing water every few days, or may remain moist in cooler seasons for longer periods of time. Water your moth orchid according to its need, not your schedule.

TEMPERATURE AND VENTILATION Most phals are happy with warm temperatures of about 75-80 during the day, and around 65-70 at night. A drop in night temperatures (to about 55-60) for a month, especially during the fall or spring will induce flowering in season. A Wireless Min/Max ThermometerA will make this easier to track. Make sure that there is always adequate ventilation and air circulation, particularly in the winter, or during very humid conditions, in order to avoid fungal and bacterial disease. However, do not subject plants to blasts of cold or hot air. An oscillating fan that moves air constantly at low speed is extremely beneficial.

HUMIDITY Phalaenopsis, like most tropical orchids, like humidity, so try to maintain about 60-70% humidity, Plants will generally not do well with less than 50% humidity. Stand plants on water-filled trays of gravel (making sure plants do not sit in water), and spray plants with water during warm dry weather in order to increase humidity. Remember, most orchids can tolerate higher temperatures if the humidity also rises.

Candystripe Phalaenopsis

LIGHT Moth orchids like bright indirect light. They will thrive in eastern, or shaded western or southern exposures. Do not place phalaenopsis in full sun. Let the foliage be your guide: leaves should be medium green, and firm. Floppy dark green leaves means that the phals are not getting enough light. Dark reddish pigmentation on the leaves may indicate excessive light which can result in fewer and smaller flowers.

Healthy green foliage- shiny and firm leaves.

FERTILIZER Phalaenopsis will do well with regular fertilizing, but will suffer if excess fertilizer is applied. As a rule of thumb, apply house plant fertilizer at half the strength recommended for indoor plants. If you are using a special orchid fertilizer, for phals potted in a bark mix, use an orchid fertilizer with a higher nitrogen content (such as 30-10-10). or a 'urea-free' formulation. For plants in a peat-based mix, or sphagnum moss, use a standard 'balanced' with a 20-20-20 formulation.

In both cases, switch to a blossom inducing fertilizer (such as 10-20-10) once new leaves have matured, generally in the later summer and continue to use this during flowering. Alternatively, switch between fertilizers each time you feed. Fertilize plants 2-3 times a month during the warmer months and 1-2 times per month during the winter when growth is slower.

FLOWERING Once a flower spike emerges it will take a month or two to mature. Stake this spike gently as it grows to ensure that the spike gets some height before it produces buds. Continue to give plants bright light. Also do not change their orientation to the light once the first buds can be seen as this will cause them to twist about and spoil the otherwise prefect symmetrical display. Buds will eventually emerge along the spike, and open in succession. Do not subject moth orchids to sudden temperature changes as this may cause buds to drop. Make especially sure plants do not dry out, as this may also also cause bud blast. Moth orchids are especially susceptible to small amounts of gas often leaking from heating units etc. in the home. This can cause the flowers to wilt and buds to drop. Basically if your plants are setting buds, do not fuss with them, other than keeping them well watered. When 3/4 of the buds have opened, you can move the plants elsewhere to enjoy the display. Flowers can last for up to three months. Once the flowering display is finished, cutoff the spike about an inch from the base of the plant. Please see our general tips if your phalaenopsis will not bloom.

Phal. Newberry Parfait 'Picotee' AM/AOS

REPOTTING Repot plants about every 12-18 months, or when the mix decomposes. Use a mix of 2/3 medium fir bark with 1/3 coarse perlite, or a mix especially formulated for phals. Be careful not to break the roots when you repot. Repot the plant in a slightly larger pot if needed. Remember that most orchids like to be somewhat pot-bound. Make sure the base of the plant is just at the surface of the potting media, not buried, and that the plant sits firmly in the pot. Keep plants more shaded than usual for a few weeks while they adjust. Healthy roots are firm and white with green growing tips. Dry, brittle roots indicate underwatering. Soft, mushy, or decayed roots most likely indicate overwatering.

PESTS AND DISEASES Most insect pests can be gently washed off, or swabbed with alcohol. Mealy bugs and scale are especially fond of phalaenopsis and like to hide in the leaf axis so examine these carefully. If necessary, use an insecticidal soap or fine horticultural oil formulated for orchids, after reading all directions and warnings carefully. Moth orchids but are susceptible to bacterial and fungal infections which can result in brown spots or rotted areas on leaves, which can quickly lead to the demise of plants. Carefully cut out infected tissue at the earliest sign of infection with a sterile blade, and spray plants with a fungicide/bactericide such as Physan. Sprinkling the affected areas with cinnamon will also help. Good culture will eliminate most problems.

A wide variety of phalaenopsis are available from online orchid vendors