Healthy, happy orchids are the royalty of houseplants: breathtakingly beautiful, long-blooming, and elegant in fragrance and form. These glorious houseplants have the reputation for being prima donnas, but nothing could be further from the truth. This group of plants – (there are over 24,000 species of orchids!) – require little care and even less water! If you know the basic rules for helping your indoor orchids bloom and grow, you’ll do just fine. Read on for the essentials about caring for an indoor orchid.
How to Care for an Indoor Orchid
Orchids (family Orchidaceae) grow in the wild in warm regions of Asia and Central and South America, but in the US the huge majority are grown indoors. Despite the size of the orchid family, the many and varied species have several characteristics in common: a protruding petal that looks like a lip in a blossom with three petals and three sepals. Sometimes the petals and sepals are fused together.
Orchids naturally grow in the wild as either epiphytic – air plants attached to trees that get water from the sky – or terrestrial with roots in the ground. And they all look different since each one has evolved to appeal to their particular pollinator.
Indoor orchid care involves appropriate light exposure, irrigation, temperature, soil and fertilizer. There are also special procedures to follow to encourage rebloom once an orchid has ceased flowering.
Orchids require shallow planting and prefer bright, indirect light. Insufficient light results in poor flowering. However, too much light can lead to leaf scorch.
Orchid Light Requirements
All orchid light requirements are the same for all species: they need bright, filtered light whether inside or outside. This is a must for indoor orchid plants if you want flowers, and of course, everyone growing orchids wants flowers. Inadequate light is the most common culprit when orchids fail to bloom.
What does this mean in a house? Place the plant near an east or south facing window where it gets strong indirect light. Don’t let the sun hit the leaves directly or they will burn.
If you have a moth orchid (Phalaenopsis), select a spot with lower light. These plants grow on trees in the wild in the shade of a tropical forest. They do best in an east or west window.
How to Water an Indoor Orchid
Orchids are not generally super thirsty, since most of them have organs for storing water. One exception is Phalaenopsis – moth orchid – that lacks these specialized bulbs, so it requires slightly more attention to irrigation.
Water an indoor orchid every week during the growing season, giving the plant enough water so that it leaks out from the pot’s bottom drainage holes. Once the orchid stops blooming, you can cut back on water, since the plant is resting. If you have an orchid with a very small pot, you may need to water twice a week when the plant is actively growing.
Orchids need ample water but should be allowed to dry out some between waterings. One way to check for watering is by poking your finger about an inch (2.5 cm) into the growing medium. If it’s dry, give it some water. Otherwise, let it be.
Ideal Orchid Temperature & Humidity
Orchids are not all alike when it comes to preferred temperatures. Some types, including some slipper orchid species (Paphiopedilum), prefer cooler temperatures, between 60 and 75 degrees F (15.5 and 24 C) during the day.
Other slippers and some moth orchids like the temperature between 70 and 80 degrees F (21 and 26.6 C) during the day, while most moth orchids like to between 75 and 85 degrees F (24 and 29 C). When in doubt, assume your plant is in the middle category. All orchids require the temperature to be 10-15 degrees lower at night.
It is very unusual for an average home to be humid enough to suit an orchid, since their ideal range is between 50 and 70 percent. Raise the humidity for your plant with a pebble tray, a humidifier, a terrarium or by grouping it with ferns. Misting the plants daily is helpful. Note that orchids also require air movement to thrive, so use a fan to gently move air.
Best Soil for Orchids
The best soil for growing orchids is… no soil at all. Houseplant orchids are usually air plants and will die if planted in regular soil. Instead, use soilless mixtures with great aeration and drainage, or purchase a special “orchid mix.” There are several types of growing media that can be used with orchid plants: redwood or fir bark, sphagnum peat moss, rocks cork, charcoal, sand, or soilless potting soil. A basic mix for growing orchids might consist of coarse perlite, fir bark, and sphagnum moss. Adding charcoal is also an option.
Generally, the grade of bark you add to the mix depends on the type of orchid you are growing. For instance, phalaenopsis orchids are usually grown in coarse bark, cattleyas in medium bark, and young orchid plants are best grown in fine bark.
Alternatively, attach the orchid plant to a chunk of bark or cork to let it grow as an epiphyte.
How to Fertilize an Indoor Orchid
Orchids need fertilizer when they are actively growing and flowering, but they will not appreciate it in excess.
Use a water-soluble fertilizer specifically formulated for orchids. If you have your orchids growing in bark, get a fertilizer with a higher ratio of nitrogen, such as 30-10-10 or 15-5-5. Other orchids do well with evenly balanced formula fertilizer ratios, such as 20-20-20. Apply these fertilizers according to the labels’ instructions. After flowering, stop the fertilizer until new leaves start growing.
You can fertilize orchids weekly or bi-weekly while they are producing new growth. Decrease the feedings to monthly or bi-monthly intervals once they mature. Discontinue fertilizing them altogether once the plants go dormant.
How to Make Orchids Rebloom
Understand your plant’s blooming cycle. Some bloom once a year, others all year. The best way to help your orchids rebloom is to give them the right environmental conditions including light, temperature, humidity, airflow, water, and fertilizer.
Repotting Orchid Houseplants
If your orchids suddenly stop blooming but have all the suitable growing conditions, repotting may be necessary.
Repot orchids every other year or more to prevent root rot issues and to make room for a growing root system. Remove the orchid from the old pot and get the potting medium away from the roots. Soak the roots, then cut out dead, soft or hollow roots.
You may be able to reuse the orchid’s container, but if you can’t squeeze the root mass back in, go up one pot size. Hold the orchid in the container and add coarse soilless potting medium, using a pencil to get it between the roots. When done, water the newly potted plant thoroughly.
Common Problems, Pests & Diseases
Sadly, orchid problems do exist, and the plants are not immune to pests and diseases. You can expect mealybugs, spider mites, scale, thrips, and aphids. These can usually be washed off or treated with insecticidal soap. You may see snails and slugs too.
As far as orchid diseases go, you may see leaf spots, petal blight, bacterial soft rot and many different viruses.
Best Types of Orchids to Grow Indoors
There are thousands of orchid species, but moth orchids are the easiest to find in the garden store and the easiest to grow indoors. Other popular indoor orchid varieties include: