An avid gardener for over 40 years, Dolores has landscaped for private clients and maintained one client's small orchid collection.
Phalaenopsis (Moth Orchid)
Orchids are amazing flowering houseplants. Once considered a luxury, these elegant plants have become affordable due to large scale hybridization. Moth orchids, or Phalaenopsis, in particular, have been bred to thrive indoors.
Of all orchids, these are the easiest orchids for beginners and are readily available and relatively inexpensive. Flowers come in a wide variety of colors and color combinations. (The weird, intense blue orchids often sold at big box stores are not naturally blue but chemically treated.) Moth orchid blooms are long-lived, lasting from 6 weeks to 3 months with proper care. Blooms appear on the end of a long, arching stem.
The foliage is sturdy and attractive. The thick leaves grow low, are long and oval in shape.
When buying this type of orchid, it is best to shop at a nursery or gardening center to ensure the purchase of a quality product. If you want a bargain and pick one up at a grocery store or the gardening center at a large hardware store, buy the orchid when it first comes in; the flowers will last longer and the plant will be in its best condition. Phals and other types of orchids are also available to purchase at specialty shops, and orchid shows.
Check the container. Phals should be planted in a loose growth medium, never in soil. Regular potting soil is too dense for the roots. In nature, Moth orchids are epiphytes, which means they grow in the crooks of tree branches filled with plant debris. They do not grow on the ground in soil.
Moth orchids grow best in pine chips, sphagnum moss, or small pieces of volcanic rock as a growth medium. A mixture of all 3 works well. Sphagnum moss alone may break down too quickly to be effective and can retain moisture for too long causing the roots to rot.
A few roots protrude from the top of the pot. They should be silvery green with green tips. Avoid buying plants that are lightweight as they are too dry. Avoid plants with shriveled looking leaves or leaves with spots, webbing, yellow or brown marks.
Make sure the container has a drainage hole at the bottom. Orchid pots should also have some holes in the sides.
A plastic pot will hold moisture while terra cotta may allow the plant to dry out too quickly. Since these plants often come in small size pots and may be top heavy, place the plastic pot into a larger, heavier, more attractive container.
Best Light for Your Orchid
Placement is very important for the health of a moth orchid. Set the container in a spot that receives filtered or indirect sunlight. An East or North-East facing window is best, though the East facing window may provide a bit too much sun in summer. If the sun shines too brightly during the summer, use sheer curtains on the window.
Do not allow them to receive direct sun, and never place the plant in a South facing window. Some sites suggest a West facing window, but the afternoon sun there can be too strong and may damage the plant.
Check the leaves of your plant to see if they are set in the best light. Healthy leaves should be grassy green. If they are very dark green, long and floppy they are not getting enough light. If the leaves look yellow, they may be getting too much light. Leaves with reddish edges indicates the plant is getting too much light.
Temperature and Humidity for Your Orchid
One of the reasons that moth orchids do so well for so many people is that they thrive in temperatures we enjoy in our homes—between 60 - 85 degrees Fahrenheit. Of course, heat and air conditioning dry out the air in many homes. To increase humidity, place the plant on a tray of moist pebbles. Do not fill the tray with water or allow the bottom of the container to sit in water or the roots will rot.
If you just have one or two orchids, placing them near other houseplants can help increase the humidity as well.
A humidifier is better for your plants than a pebble tray. Water in a pebble tray will increase the humidity in a small area while a humidifier effects the whole room. Humidity ranges of 40% - 70% are optimal for orchids. Use a small fan to create air movement to deter fungal problems. A paddle fan on the lowest setting or a small fan work well. Do not direct the fan toward the plants.
A drop in temperature will signal Phalaenopsis to bloom. Some believe that cooler nights do the trick, while other experts claim a general all day temperature drop encourages bloom production.
A plant set in an East or North-East facing window should experience this temperature dip in the Fall.
Do not allow your orchid to sit in a drafty area or experience temperatures below 55 degrees Fahrenheit.
Some successful moth orchid enthusiasts place their plants outdoors in summer. If you choose this route, keep the plants well shaded. Bring the plants indoors before evening temperatures go below 60 degrees F. (The weather report may predict a 60 degree F night, but could easily be wrong)
Moth Orchid and Water
Sphagnum moss retains moisture longer than pine bark or volcanic rock. So plants grown in sphagnum moss should be watered less than plants grown in a looser medium. This is not the preferred planting medium for moth orchids as it can retain too much moisture and become soggy.
How To Water Your Orchid:
- Run tap water into a large container and set out overnight or for 24 hours to off-gas chlorine. Allowing it to sit overnight will bring the water to room temperature. Do not water the plants with cold tap water.
- Set the inner, plastic container in a sink and water until all the water drains out the hole in the bottom of the pot. Repeat.
- Make sure water does not collect in between the leaves. Tip plant to drain. If water remains between the leaves at the top of the plant, this can cause crown rot.
- Dust the leaves when you water the plant.
How Often Should You Water?
This depends on several factors:
- How dry is the air in your home?
- Are the pots made of plastic (holds moisture) or terra cotta (dries out more quickly)?
- Does the soil mix dry out quickly?
Most tropical plants enjoy a brief winter rest. In the colder months, water every 10 - 14 days.
In Spring and Summer, water it once a week or so.
You can often tell if the plant is dry by weight. When the plant is first watered, notice how heavy it feels. When the container feel light, it's time to water. Another method is to stick your finger into the medium to feel for moisture. Sometimes the top may seem dry, but still damp lower down.
Remember that the number one killer of houseplants is over watering.
Fertilizer for Phalaenopsis
- Fertilize with a liquid orchid food once a month in spring, summer, and early fall.
- Or, mix up a batch of 1/4 strength fertilizer to feed weekly.
- Before you fertilize, flush the plant with water. Then add the liquid fertilizer.
- Use only fertilizer that is for orchids.
- Some growers like to add crushed egg shells once a season. If you do this, first wash and dry the shells. They can be quickly ground up with a mortar and pestle.
Moth Orchid: New Spike
The flower stalk grows up from the base of a leaf. The first indication is just a little bump. The spike is a light, bright green in color. (Note the photograph above) Don't confuse air roots with a spike. The roots have a silvery sheen while the spike does not.
Here is how to guarantee the success of your flower:
- Make sure that the flower stalk is staked. The flowers grow at the end of a long stem and may hang over, making the plant top-heavy.
- Gently twist a thin bamboo stake between the roots. As the spike grows, clip it to the stake with tiny hair clips (those hinged, plastic ones with the teeth).
- Once the flower stem begins to grow, do not turn the pot but keep it oriented in the same direction. The stem will grow toward the light. Constant turning will cause the stalk to twist in an unattractive manner.
- When the flowers are in full bloom, you may move the plant however you like for optimal viewing.
- Maintain water and feeding.
What To Do About Dying Flowers
When the flowers die off, there are 2 courses of action you may take:
- Cut back the stem close to the base. Use a sterile knife or scissors. To prevent fungus problems at the cut, dab a bit of cinnamon on the tip.
- Or, cut the stem back to a node—a little line and small bump below the spot where the lowest flower grew. This encourages new flowering.
In any event, remove the spike when it becomes woody.
Please Note: Flowering takes a lot of energy from the plant. Many orchid lovers like to encourage the plant to rest, and are satisfied with a once a year bloom. After all, the flowers last a long time.
Repot a Moth Orchid
- Never repot when the plant is in bloom!
- Repot when the planting medium begins to decompose.
- Turn the plant over. Gently remove orchid.
- Gently shake off the old medium.
- Snip off any dried up or dead looking roots.
You do not need to plant Phalaenopsis in a large pot. But a slightly larger container gives the roots room to spread out a little.
Moth Orchid Problems
- If your Phalaenopsis dies, get another one and try again. You never really fail with any plant unless you've killed 3 of them. We learn from our mistakes!
- If a plant is infested with insects, throw it out! An infestation will severely weaken the plant and may spread to other houseplants.
- If you really want to rescue the plant, isolate it from other orchids or houseplants so the problem will not spread.
- If all the leaves are yellow or browning, or if the foliage has a shriveled appearance, throw it out. The plant will not revive.
- If the plant produces new leaves, but the lowest leaves turn yellow, remove the lowest, yellowed leaves. In this case, there is no problem, it's just that the bottom leaves have aged.
- Yellow or brown leaves will not turn green again.
- If all or most of the leaves appear shriveled, they will not revive.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
Questions & Answers
Question: What does it mean if the orchid flowers are dying?
Answer: No flower lasts forever. Phal blooms can last a long time but will eventually die. Cut back the spike after the blooms are gone. While some people leave part of the spike to encourage more blooms, most plants need a rest so I advocate cutting back the spike to the base. Make a paste of cinnamon and water and smear it on the cut area. This will help prevent fungus. In general, Moth orchids bloom once a year.
The flowers should last six weeks. If your blooms die before that, you may have purchased a plant that has already been in bloom for some time. Bud blast is when the blooms shrivel and die early. This can be caused by cold drafts, smoke, over or under watering, temperature extremes or a sudden change in temperature. Bud blast can also occur with too much sun or not enough sun, Fumes from ripening fruit, chemicals, or too strong application of fertilizer or fungicide can also cause bud blast. Moth orchids need moisture so a very dry atmosphere can also cause the buds to die.
Question: What is wrong that my Moth Orchid grows an abundance of foliage but barely flowers? It has large and long leaves, but the flowering is very skimpy.
Answer: Large. long leaves in phalaenopsis orchids along with a lack of flowers usually indicates that the orchid is not getting enough light. The leaves grow large seeking light. Remember that low light means does not mean no light. Try moving the phal to a north-facing window. An east-facing window works well too as long as the plant does not get direct, bright sun. Shade the east window with sheer curtains.
A typical moth orchid will flower once a year, some bloom more often. The American Orchid Society says that fall or winter temperatures that drop no lower than 55 degrees Fahrenheit will encourage blooms. Other sources claim that it's a nighttime temperature drop of up to 10 degrees F that does the trick. While it can be difficult to create such conditions in the home, you can place your moth orchids in a room with the heat vents closed in winter. Keep the door open during the day to allow warmer air of the home into the room. Close the door at night. Do not allow the plant to experience temperatures below 55 degrees F.
Some experts suggest that the short days of winter encourage blooming.
As with most plants, you might have to find the right spot in your home. Make sure there is adequate humidity and air movement.
© 2013 Dolores Monet
Dolores Monet (author) from East Coast, United States on November 15, 2017:
Hi Pamela - if any plant is in bloom, leave it alone until the flower dies. If it is in a glass vase, is it just the flower on a stem? If it's just a cut flower there is not much you can do but enjoy it. If there are roots, follow the advise in the article. You don't want to keep a rooted plant in moss but in an orchid medium which is like chunky bark. Moss rots quickly and holds too much water. Moth orchid roots want to dry out between watering. Good luck!
Pamela Demas on November 14, 2017:
My first moth orchid is in a glass vase , no drainage or soil just moss, and is in bloom? What now?
Dolores Monet (author) from East Coast, United States on October 24, 2013:
starstream - good for you that it's still around. Follow my advise above and hope for the best. Pay close attention to the proper light, feeding, and the changes needed in temperature and light to encourage your orchid to flower again. Good luck!
Dreamer at heart from Northern California on October 18, 2013:
I enjoyed your orchid article. My little orchid is now living in year 2. I am so glad it is still alive... BUT... I cannot see any new bloom shoots. What can I do to get another flower? Thanks so much. I love orchids and wrote an article here about painting orchid pictures.
Dolores Monet (author) from East Coast, United States on September 03, 2013:
Hi drbj - thanks for stopping in. I should have mentioned that Phals are called Moth Orchids because some think that the bloom resembles a moth with open wings. I don't.
drbj and sherry from south Florida on September 01, 2013:
Thank you, Dolores, for these easy-to-understand instructions about the proper care for the Phalaenopsis orchid. But why is it called the Moth orchid? Is it the favorite corsage for lil boy moths to give to little girl moths at prom time? Just wonderin'.
Great photos as usual, m'dear.