Phalaenopsis Orchids (moth orchids) are among the most popular houseplants due to their unusual growth and striking flowers in various vibrant colors. Fortunately, Orchids do pretty well when grown in our homes!
Although Orchids grow very differently from other houseplants, caring for them is not that different. Understanding Orchids' origin and natural growth patterns are essential in understanding why they grow the way they do and how we can mimic their natural environment in our homes to get those fantastic flowers year after year.
What Makes Orchids Different From Other Houseplants?
Orchids are epiphytic plants, meaning they grow on other plants. Their natural habitats are the tropical forests of southeast Asia and Australia which provide them with constant moisture through frequent rainfalls and high humidity.
Orchids grow thick, aerial roots that wrap around the tree branches they live on. These roots absorb nutrients from their surroundings from animal droppings and decaying organic matter. Their roots even have photosynthetic capabilities!
Orchid flowers are breathtaking and come in a variety of vibrant colors. These flowers can stay in bloom for months given the right conditions.
Orchids produce monopodial flowers, meaning they grow from one stem or ‘spike’. This spike is often sold clipped to a stake. The purpose of the stake is to keep the spike upright as it can become top heavy with a full show of flowers.
It is not uncommon for one plant to grow multiple flower spikes at once. The common Phalaenopsis (moth orchids) are the only Orchids that are able to re-bloom on the old spike if kept alive. These flower spikes are known to die back after the flowers have dropped off, but
Sometimes they will stay alive and flower multiple times on the same spike. Therefore, it is best to keep the spike intact to see if it chooses to re-flower. Cut it to the base near the leaves if the spike begins to brown and die.
These same spikes can branch out, forming multiple buds down the spike. If your spike forms more buds down the spike after its first flush of flowers at the top, cut back the spike right above this bud. This is where your new flowers should form.
Why Isn’t My Orchid Flowering?
We often see people’s Orchids sitting in the corner of a room being ignored because they haven’t re-bloomed. It is essential not to forget about your Orchid after it blooms and care for it like any other plant. If you give your Orchid all the correct type of love, it should re-flower. If your Orchid has re-flowered, it could be from:
A lack of sunlight (Orchids grow best in bright, indirect sunlight from south or east-facing windows. Supplemental lighting from grow lights or fluorescent lights can be used in homes with low lighting.)
Insufficient fertilization (Orchid-specific fertilizers should be applied once every other watering. Add a water-soluble fertilizer to your watering can or water bath.)
Lack of low temperatures in the winter (Orchids need a slight drop in nighttime temperatures no lower than 55°F in the fall or winter to produce flowers the following spring.)
Orchids have thick roots that don’t absorb water as quickly as other plants, and since our homes are drier than their natural environments, the roots must get a good soaking to absorb enough moisture. Since most orchid specific pots are designed with holes, they cannot be watered like other plants. Everyone seems to have their method of watering Orchids, but what we have found to be the most effective is to soak the roots in a water bath every two weeks for about 45 minutes.
If the leaves on your Orchid are leathery, wilted and wrinkly, it is showing you that it is thirsty. Once you give the roots a good soaking, they will plump back up. Placing a small humidifier near your Orchid will help it absorb moisture in all parts of the plant, especially during the winter months when the heater is on.
Re-potting an Orchid
Orchids are often sold root bound in small, plastic pots. If kept in these pots, the roots will eventually suffocate from a lack of oxygen. The Orchids are often severely root bound in these pots, so you may need to cut the pot to release it from the roots. Remove any dead or rotten roots at this point (roots should be firm to the touch).
Since an Orchid’s roots like more air than other house plants, their pots are designed differently. Orchid-specific pots are made with many holes around the sides so the plant’s roots have room to grow and for better aeration. Here is one type of Orchid pot on the market. Orchids should be re-potted into these specialized pots as soon as purchased.
It is common for an Orchid’s roots to grow over the top of their pots. This is a sign that the roots have run out of room in the pot and are looking for something to climb onto as they do in nature. This typically happens in pots not designed for Orchids because the roots don’t have holes to grow through. When this happens, it is time to re-pot into a larger, Orchid pot.
Orchid Specific Soil Medium
Orchids should not be potted into the same potting soil you place your other houseplants in because the dense nature of these soils can suffocate their roots. Orchids require highly coarse potting mediums such as sphagnum moss or pine bark.
The benefit of these materials is that they allow the Orchid’s roots to spread out and breathe easily. This is the closest we can get to their natural environment in our homes. Orchids can be potted directly into either of these materials alone, but there are some Orchid specific mediums on the market, such as:
Orchid soil mediums do not provide the plants any nutrients, they simply hold onto moisture for the roots, so it is vital to fertilize regularly with orchid-specific fertilizer.
Fertilizing an Orchid
Orchid specific fertilizers have the same nutrients (nitrogen, phosphorus, potassium) as other plant fertilizers. The only difference is the ratio of these nutrients. A balanced fertilizer containing all three nutrients will provide enough nutrients to keep Orchids growing strong all year. However, growth can be manipulated by fertilizing with different ratios of nutrients.
Since nitrogen helps plants proliferate, some will fertilize with a high nitrogen fertilizer early in the year, followed by high phosphorus or “bloom booster” fertilizer later. The potassium in fertilizers helps plants fight off disease and grow healthy roots.
Because of the nature of Orchid pots and the need to soak their roots, we have found that water-soluble fertilizers work best because they can be added right to the water bath or watering can.
Here are some water-soluble, Orchid specific fertilizers:
Although Orchid care is slightly different from the care of other houseplants, a few adjustments to the environment you provide them should present you with beautiful flowers for years to come!
If you have any more questions about how to care for your orchid, we will be happy to assist you in a virtual telehealth appointment with one of our Plant Specialists. Please click on one of the options below to book an appointment.