Orchid Care: How to Grow Phalaenopsis (Moth) Orchids Indoors


How to care for orchids indoors

Phalaenopsis (Moth) are the most popular orchid to grow indoors and has blooms that can last for months. Growing phalaenopsis orchids is easy for beginners as long as you mist the leaves to create humidity, locate them in bright indirect light and plant them in a well draining aerated, pine bark potting mix.

Here is a table summarizing the main requirements of growing phalaenopsis orchids for beginners:

How to Care for Phalaenopsis Orchids Indoors:Indoor Orchid Requirements:
Best Pots for Orchids:Clear plastic pots as the roots need light.
Best Soil for Orchids:Pine bark based orchid potting mix is better then moss.
Optimal Temperature Range:65°F to 80°F (16°C to 26°C) is the ideal temperature range. Temperature fluctuations cause the flowers or flower buds to drop.
Light and Location:Bright, indirect light. Avoid any draughts or strong air currents from air conditioning.
Fertilizer:Use a specialized orchid spray fertilizer, not a multi purpose houseplant fertilizer.
How Often to Water:Water around once a week and once every 10-14 days in Winter. Orchids should be watered when their roots turn light gray.
Humidity:Phalaenopsis orchids prefer high humidity. Mist the leaves, roots and flowers regularly or use a plant humidifier.
How Often to Repot Orchids:Repot every 2 years as the potting mix decomposes which can cause the roots to die back.
How To Get Orchids to Rebloom:Trim back flower spike to just above a node. Maintain a cooler temperature of between 55°F (12°C) to 60°F (16°C) for 4 weeks and maintain high humidity.

Keep reading to learn all the best practices and for a step by step guide for how to get your orchid to re-bloom…

Best Pots for Phalaenopsis Orchids Indoors

Clear plastic pots are the best for orchids indoors as they allow the roots to photosynthesize.
Clear plastic pots are the best for orchids indoors as they allow the roots to photosynthesize.

In my experience of growing orchids indoors, the best pots are clear plastic pots (with holes in the side) and then I place the clear plastic pot inside a heavier, more decorative ceramic, clay or terracotta pot.

The reason for this is that the orchids roots are fairly unique in that they are green (or light gray) and can photosynthesize as well as draw up water and nutrients, so clear plastic pots ensure that the roots have enough light for photosynthesis to contribute energy to the orchid.

Phalaenopsis (Moth) orchids are epiptytes which means they naturally grow on trees in their native environment with their areal roots exposed to light and air.

Orchid in a clear plastic pot with holes in for added ventilation around the roots.
Orchid in a clear plastic pot with holes in for added ventilation around the roots.

Photosynthesis is usually, exclusively the function of the leaves and whilst the leaves are the orchids primary means of photosynthesis, the clear pots allow the orchids roots to provide additional energy for the plant.

Added air holes or slits in the side of the orchids pot allows air to circulate around the roots, similar to its natural environment which facilitates root respiration and helps to mitigate the risk of root rot.

Plastic pots also help you to determine whether the orchid needs watering or not as the orchids roots should appear green after watering and be allowed to dry slightly so that they turn silvery or light gray before giving the orchid a thorough watering.

The problem with plastic pots is that they are very light and with the orchids top heavy structure the orchid can topple over.

This is why I recommend placing the pot inside a heaver decorative outer pot which looks aesthetically more pleasing then a plastic pot and counter balances the top heavy orchid to prevent it from falling over.

Orchid roots are a key indicator of health, so if the orchid begins to look unwell then you can simply take it out of the outer pot and inspect its roots for signs of rot through the clear plastic pot. Clear pots are also good because you can see whether the potting mix has decomposed to the point it needs replacing (orchids need repotting every 2 to 3 years).

Ensure that the pot is at least 6 inches across to accomodate the orchids root system. It is also worth noting that the wider the pot the more stability the top heavy orchid has.

Best Soil for Orchids (Best Potting Mix)

Orchid pine bark based potting mix on the left compared with ordinary potting soil on the right.
Orchid pine bark based potting mix on the left compared with ordinary potting soil on the right.

The best potting soil for phalaenopsis orchids is a pine bark based, specialized potting mix. The pine bark chips are large in size which creates the optimal aerated well draining structure that orchids need to avoid root rot and stay healthy.

It is important to remember that phalaenopsis orchids are epipthyes that grow naturally on tree branches, using their roots for stability rather then growing on the ground in soil.

Ordinary potting soil is too dense and not porous enough for orchids and would stave the roots of the oxygen they need for root respiration. Ordinary potting soil also retains too much moisture around the roots for orchids to tolerate.

Pine bark chips are also quite large which creates the space for the roots to grow and establish through the mixture, whereas other potting soils are simply to dense for the orchids roots to grow.

I personally recommend using miracle-gro peat free orchid compost which is composed almost exclusively with pine bark chippings.

It is worth remembering that moth orchids grow on the bark of trees in branch up in the canopy of their native humid tropical environment so pine bark based potting soil is the potting medium that most closely emulates their natural growing conditions.

Pine bark based potting mixes are better the peat moss for growing phalaenopsis orchids. A lot of commercial growers use peat moss as it is cheaper then pine bark, however, it decays more quickly, meaning that you would have to repot more often and typically it holds moisture for longer which can increase the risk of root rot.

Best Temperature Range For Orchids Indoors

The best temperature range for orchids is between 55°F (12°C) and 75°F (23°C) so around room temperature is best for phalaenopsis orchids. If the temperature is significantly higher or lower then this range, then the flowers or flower buds are likely to drop off.

Phalaenopsis orchids prefer a cycle of warmer days and cooler nights within this temperature range as it replicates the typical temperature cycle in their native environment, so be mindful of this as indoor heating or air conditioning reverse this natural cycle.

Phalaenopsis orchids grow in conditions with very consistent temperatures so any fluctuation in temperature from open doors or cold draughts can prevent the orchids from displaying blooms.

Phalaenopsis orchids need a period of cooler temperatures around 55°F (12°C) to 60°F (16°C) for 4 weeks to stimulate flowering. (Scroll down to the section of reblooming orchids for more information).

I should emphasize the importance of ensuring that the orchid’s leaves should not be in contact with glass as the glass can be much colder at night then the ambient temperature of the room. if the leaves are in contact with the window they can turn yellow or brown depending on how cold it is.

Best Light and Place to Position your Moth Orchid

Orchids prefer bright indirect light.
Orchids prefer bright indirect light.

Moth orchids need to be in bright, indirect light when grown indoors. The orchid needs the bright light for photosynthesis and to stimulate flowering.

Phalaenopsis orchids naturally grow in the canopy in bright light, but with protection from intense direct sunlight.

If the orchid does not have bright enough light then it is unlikely to flower. However if the orchid is in a sunny South facing window then the sunlight scorches the leaves yellow or brown (depending on the intensity of the sun).

If the orchid’s leaves scorch then they do not turn green again and recover their appearance, hence the importance of finding the right balance of bright indirect light.

Locate the orchid out of the direct path of air conditioning, open door or near any sources of heat. Orchids do appreciate the occasional gentle breeze from an open window as air circulation is good for the leaves and roots.

Orchids are native to humid climate so humidity is also greatly appreciated which is why orchids are often grown in more humid rooms of the house such as bathrooms.

However, as long at the orchid is kept out of any strong air currents then you can create humidity by misting the leaves or using a humidifier.

How to Fertilize Orchids (For More Orchid Blooms)

I find a mist spray fertilizer is best for growing orchids indoors.
I find a mist spray fertilizer is best for growing orchids indoors.

Orchid roots are particularly sensitive and do not tolerate regular houseplant fertilizer as this could burn the roots, however orchids are heavy feeders and need additional fertilizer to promote vegetative growth and of course for flowering.

Therefore the best fertilizer for phalaenopsis is a specialized spray product. Phalaenopsis orchids grow on trees in their natural environment and their roots absorb nutrients in the humid air or from organic matter in the surrounding area.

A specialized orchid fertilizer contains the right nutrients that the orchid needs at the right concentration to support growth and promote flowering. With a spray product you can spray the orchids aerial roots effectively replicating the way orchids absorb nutrients naturally.

With the product I use, I spray the roots with fertilizer every 2 weeks during active growth in the Spring and Summer and then once a month during its Winter ‘rest’.

Little and often is the best approach to fertilizing phalaenopsis orchids as this mimics the typical way the aerial roots draws in nutrients in its native environment. Do not use more fertilizer then the manufacturer recommends as this can cause your orchid stress.

Orchids are capable of flowering at anytime of year in their native environment but indoors they typically have a more dormant period in Fall and in Winter in reaction to the decreasing hours of daylight which is when you should reduce the frequency of fertilizing.

This ensures the orchid has all the resources it needs for a good display of flowers

How to Often to Water Moths Orchids

Orchids Indoors:How Often to Water Phalaenopsis Orchids:
Orchids in Spring and Summer:Water indoor potted orchids once per week during active growth.
Orchids in Winter:Water once every 2 or 3 weeks in Fall and Winter.
Mist the Orchid Leaves:Mist the orchids leaves and roots with water at least 2 times per week to create a humid, tropical micro-climate.

The best water to water orchids is by watering with a generous soak with the goal of ensuring all of the orchids potting medium is evenly moist after watering. Always water your orchids at the roots rather then overhead watering to prevent crown rot.

Crown rot is a common problem associated with watering phalaenopsis orchids as as the leaves of these orchids create a funnel shape which channels water to the crown where it pools and causes rot.

Orchids grow at an angle in their natural environment so that the rainwater can drain away but indoors orchids are grown upright hence the prevalence of crown rot.

However it is important to note that in my experience, how often you water your orchids can vary according to several factors such as:

  • The average humidity and temperature range of your home.
  • The size of your pot or container (smaller pots dry out much quicker then larger pots, read my article, choosing the best pots for orchids).
  • Whether the orchid is near sources of heat.
  • The type of potting soil (moss retains more moisture then bark).

Whilst watering every 7 days in generally good advice, in my experience I find the best way to establish whether your orchid need watering is to look at the roots.

After watering the roots should be a healthy green colour, and then the roots should turn a light silver/gray as the roots and potting medium dry slightly.

Once the roots have turned silver or light gray, give the orchid a generous soak and mist the leaves and any aerial roots that are growing out of the pot.

Green, healthy phalaenopsis roots after watering.
Green, healthy phalaenopsis roots after watering.

Watering this way achieves the balance of providing the orchid with enough water to meet is requirements whilst also avoiding the problems associated with overwatering.

I always recommend growing orchids in clear plastic pots so you can assess the colour of the roots and determine whether the orchid needs to be watered.

I recommend always watering with lukewarm water. Phalaenopsis orchids are tropical plants and can suffer shock if the water is too hot or too cold.

I must emphasize that regularly misting is important all year round as low humidity causes the orchids buds to drop before opening. Consider how humidity changes during the year in your home, with indoor heating sapping moisture from the air in Winter and increase the regularity of your misting accordingly.

You can also use a plant humidifier which creates a humid micro climate around your orchid to keep it healthy.

If you are unsure about watering read my article, How to Tell Whether your Orchid is Under or Overwatered (With Photos).

Do not Water Orchids With Hard Tap Water

Orchids are especially sensitive the build up of minerals around the roots when they are water with mineral rich or hard tap water.

Therefore it is important to water orchids with rainwater, distilled water or bottled water, however watering occasionally with tap water is unlikely to cause an problems and generally watering with soft water is okay.

Consistently watering with hard tap water can eventually turn the orchid’s leaves yellow and prevent the roots from up-taking water and nutrients.

Therefore I recommend looking on google to establish whether your tap water is hard or soft and water accordingly.

How Often to Repot Moth Orchids

In my experience, it is best to repot phalaenopsis orchids once every 2-3 years if they are planted in a pine bark based potting medium and once every 1-2 years if they are planted in peat moss.

Pine bark decomposes more slowly then peat moss hence why the orchid should not need repotting as often.

Clear plastic pots are very helpful when it comes to assessing whether the potting medium has broken down to the extent it needs repotting.

If you do not repot your orchid the pine bark or peat moss deteriorates to a soil like consistency which reduces air circulation around the orchids roots and retains too much moisture, potentially killing the orchid.

Whether or not the potting medium needs replacing, sometimes it is necessary to repot orchids if their roots are clearly restricted and pressing up against the side of the pot.

How to Repot Phalaenopsis Orchids

It is possible to successfully repot orchids at anytime of year, but I personally recommend repotting after flowering as the stress of repotting can sometimes cause the flowers to wilt or drop off.

If the roots of the phalaenopsis are clearly pressing up against the side of the pot and clearly look constricted then ensure that the new pot is about an inch wider in diameter.

I must emphasize that orchids have aerial roots, that are there to extend out of the pot as they can would naturally in their native environment.

In their home range, the aerial roots provide additional stability, absorb moisture from the air and photosynthesize, so some roots extending out of the pot is totally normal and not necessarily cause to repot your orchid.

Sometimes it may not be necessary to replace the pot, just the potting medium (if the potting medium has decomposed).

Do not choose a pot that is much larger then 1 inch across bigger then the pot as larger pots can retain much more water then the orchid is used to which can increase the risk of rotting roots.

Larger pots with more growing medium can also cause the orchid to prioritise directing its energy into root develop rather then to grow flowers

Once you have selected your pot take the orchid out of its container and tease away any existing potting mix.

In my experience it is best to run the roots under a facet (tap) to wash away any stubborn part of the potting mix that cling on and running it under water makes the roots more flexible and easier to manipulate.

Running the roots under water should also turn the healthy roots green, however it should be noted that roots can be whitish or even yellowish and still be healthy.

The roots that are white or yellow may not have had access to sunlight which has decreased the amount of chlorophyl (which is the pigment responsible for their green color) whereas roots with access to light should be green.

Feel each root individually. The healthy roots should feel firm when you squeeze them. If they feel spongy and somewhat limp then these roots are dying and you should cut them back to healthy growth (or to the base) with a sharp pair of pruners.

Once the roots turn squidgy they do not absorb water or nutrients, therefore do not help to sustain the orchid.

This prevents them decomposing and causing problems in the new potting medium.

Some orchid roots do die from time to time as part of their natural cycle and as long as all the other roots feel firm and healthy then it does not necessarily indicate there is anything wrong with the plant.

Once you have cleaned the orchids roots, place the orchid in the new pot and fill in the pine bark potting medium around the roots.

The pine bark chips are sufficiently large in size that air can circulate around the roots and retain the moisture that phalaenopsis roots require.

The pine bark chips hold moisture and then it evaporates creating a humid micro climate around the roots emulating the orchids natural environment.

Try to ensure that there are no significantly large air pockets around the roots as too much air flow can dry the roots out.

Repotting in a transparent pot is the best way to see if the orchid has enough potting medium around the roots and that it is well distributed.

Water the newly repotted orchid with a generous soak and mist the leaves generously to help mitigate transplant shock.

How to Care for Phalaenopsis Orchids to After Blooming (And Get Them to Rebloom)

Phalaenopsis orchid blooms can last up three months in the right conditions before dropping its blooms.

The phalaenopsis can sometimes rebloom on the same flower spike if you cut the flower spike just above the second node under the spent flowers, which can stimulate a side shoot to from on the flower spike from which new flower buds emerge.

Cutting half an inch above the node of a phalaenopsis orchid can grow a new flower spike to display more blooms.
Cutting just above a node (which is by my index finger) can promote the growth of a side shoot from which more flowers can be displayed.

However sometimes the flower spike turns yellow and dries out, which is a normal part of the orchid’s life cycle, at which point you can carefully cut the spent flower spike back to the base with a sharp pair or pruners.

The orchid then has to grow a new flower spike before new flowers can then be displayed.

In order to stimulate the development of a new stem and new flowers the orchid has to experience a specific sequence of temperatures.

It is important to replicate the phalaenopsis orchid’s natural temperature cycle to initiate new blooms by decreasing the temperature to between 55°F (12°C) to 60°F (16°C).

The cooler temperatures indicate to the orchid that this is this is the right time of year for flower development.

Place the orchid in a cooler room for 4 weeks with bright light and some humidity, then you can return the orchid to its usual location with warmer temperatures.

This method is so effective that commercial orchid growers always control the climate conditions in order to sell orchids that are in flower at anytime of year.

In my experience, temperature is by far the most important influencing factor to get orchids to flower again.

Because of these specific temperature requirements, phalaenopsis orchids growers often struggle to get their orchids to rebloom in warm climates, whereas some growers do not have to put any effort into stimulating new flowers as their climate and household temperatures naturally follow this temperature cycle.

When growing orchid at home I find the new flower spike typically grows in Winter and the orchids flowers are displayed early Spring and last for 3 months with frequent watering, high humidity (by regularly misting the flowers, aerial roots and leaves).

(Read my article for more information how to rebloom orchids indoors).

Orchid Blooms Falling Off

Avoid any drastic fluctuations in temperature and humidity during bud development and flower displays as this can cause the buds and flowers to fall off.

Typically this means, avoiding any draughts from cold blasts of air from open doors and avoid locating orchids in the direct air current of air conditioning or heating.

For more information read my article: Why are my Orchid Flowers Falling Off?

If your orchid is in any trouble read my article, How to Revive a Dying Orchid.

One thought on “Orchid Care: How to Grow Phalaenopsis (Moth) Orchids Indoors

  1. I had an orchid that I had to trim the roots due to being all dead except 1-2 roots that at the end ended up dying. Although before I gave up on the plant It had 2 healthy long stems that had roots coming out on top by the new leaves. I cut the long stems and transplanted them in a plastic water bottle actually since the stems are so thin. Is this the right thing to do? how long will it take to have actual roots so I can re plant in a actual container. Thanks!

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