Orchids are an incredibly seductive indoor plant, with a look and an appeal that has attracted enthusiasts for centuries.
Orchids have a reputation as a difficult plant to grow outside of a greenhouse, and there are some varieties that can be quite fussy.
But, with more than 100,000 orchid hybrids available, thousands of orchid varieties will thrive indoors and give gorgeous blooms year after year.
In fact, these ethereal plants are tougher than you might expect, and will thrive with the right care.
What are Orchids?
After the aster family, orchids are the second-largest family of blooming plants in the world. They occur in every environment around the world, aside from glaciers, but are most common in the tropics.
They are symbolic flowers in many cultures, and have been depicted in ancient art. And orchids are responsible for one of the most essential culinary flavors in existence: vanilla.
Orchids are famous for their extraordinary flowers, which have been cultivated and sought after for centuries. In Victorian England, “orchidelirium” developed into a full-blown craze, and orchids could cost thousands of pounds, and were kept in specialized miniature greenhouses.
Fortunately, modern orchids don’t require nearly as much care and maintenance as their wild ancestors, but there are still some things to know in order to keep orchids healthy and blooming indoors.
Pots and Planting
It’s unfortunately true that many orchids are sold in attractive pots that aren’t ideal for the plant to live in. In nature, orchids don’t live rooted in soil, and grow on the branches of trees.
In traditional potting soil, where an orchid’s roots are immersed in water and don’t have air circulation, the plants won’t bloom and may die.
What to Do
Plant orchids in an orchid potting mix, which is usually a loose mix of bark, stones, or greens that keep the soil well-aerated.
Orchids need to be re-potted after they have finished blooming, when they naturally go through a growth cycle and begin producing new roots, which may be two or three times a year. Plant them in a new pot 1-2 inches larger than the previous container.
Never repot an orchid when it is in bloom, or the blossoms will drop. If the orchid is in unhealthy soil, or a too small container, but is in bloom, simply reduce watering frequency to ensure that the roots have time to dry out and oxygenate between watering, and repot it into better conditions after it is done blooming.
Light is arguably the most important part of caring for an orchid as a houseplant, because insufficient light will not kill the plant, but will prevent blooming. Most orchids prefer 6 hours or more of daylight, but don’t thrive in direct sunlight. A sunny southern or eastern windowsill, with a sheer curtain for light shade, is ideal.
Orchids are classified as high-, medium-, or low-light varieties, depending on the intensity of light they need to bloom. High light varieties need 3,000 foot-candles of light, while low light varieties can get by on 1,000-1,500 foot-candles.
If your natural light is insufficient, a simple fluorescent tube may provide sufficient light for most low and medium light orchids,. A high light variety may need a higher intensity grow light in order to bloom.
What to Do
An orchid’s leaves indicate whether it is getting sufficient light. An orchid with sufficient light has leaves that are a light or medium green with yellow tones. Leaves that are lush and dark in color are indicative of insufficient light, even if the color is attractive. If the leaves look bleached and white, the orchid is getting too much direct sun.
Move new orchids or new orchid varieties into different light conditions, and move orchids as the seasons change, to identify and maintain the optimal light conditions for blooming. Or consider investing in an additional light source if your orchids won’t bloom in your available natural light.
Water and Humidity
As mentioned above, orchids naturally grow with their roots exposed to the air, getting water from rainfall and from the humidity in the air.
For that reason, they don’t need to be watered as frequently as other house plants, and too much watering may be bad for them.
Most orchid varieties require humidity of 50% or more to bloom, and most homes are far less than that.
What to Do
Water orchids once a week and allow them to dry between watering. It is better to under-water them than to over water them. Place them in a humid room like a bathroom, or increase the humidity near the plants by using a humidifier or by grouping orchids and other moisture-loving plants together.
You can create a humid environment for a lot of orchids at once by taking a long, flat tray and filling it with pebbles that are dark in color.
Place orchid pots on top of this pebble bed, and then pour water until it is almost at the top of the stones. Keeping the tray wet will keep the air moist, and can be an attractive way to make the most of a family of orchid plants
There are a number of factors when considering the temperature that will help an orchid thrive. Orchids generally don’t do well in temperatures over 90°. Orchids are usually classified into warm, intermediate, or cool growing, according to the lowest overnight temperatures they can tolerate.
Warm temperature orchids need overnight low temperatures of 60° or more, while cool-growing orchids can tolerate temperatures of 50°.
Finally, most orchids naturally experience a big change between day and night-time temperatures, with a difference of 10° or more that many people don’t experience in their homes.
What to Do
Along with keeping orchids out of direct sunlight, keep them away from peak daytime temperatures if they exceed 90°, and protect them from getting too cold overnight. At the same time, don’t keep them in an environment with a stable temperature 24 hours a day.
An overnight drop in temperatures won’t make the difference between a sickly orchid and a healthy one, but it may make the difference between a healthy orchid and a thriving one. If possible, lower your overnight thermostat to let them cool off overnight.
Food and Fertilizer
Orchids do best with too little fertilizer than too much, but will benefit from a general purpose fertilizer used for other indoor container plants.
A 10-10-10 formula is usually sufficient, and it should have no urea.
What to Do
Choose a water-soluble fertilizer and dilute it to ¼ strength for weekly watering.
Do not use fertilizer on a completely dry orchid root, because it may cause a fertilizer. The roots should be damp first, so the plant should be watered or misted before fertilizing.
With proper care, an orchid will bloom one to three times a year, and bring beauty and fragrance to your home. If possible, identify your specific orchid species to find out what to expect in flowering frequency, and how to provide the exact right environment for your orchid.
The good news is, once you have a place and care regimen that allows a single orchid to thrive, you will have everything you need for an entire indoor orchid garden.