My blog site is primarily dedicated to growing tropical and subtropical plants, whether as a houseplant or in the garden

Why Won’t My Orchid Bloom?

Why Won’t My Orchid Bloom?

I often interrogate people with a barrage of questions once they tell me that their moth orchid isn’t reblooming.  My educational background is in Chemical Engineering, and the focus of my day job is solving problems for my company, and teaching people how to solve problems.  So I can’t help but get to the bottom of things!

The truth is, Phalaenopsis orchids (moth orchids) are not hard to grow, and you just need to be aware of their basic needs and be consistent with your approach to care.  You can’t just plop your plant in your home and ignore it and expect it to flourish.  There are numerous reasons why your moth orchid won’t bloom.  Here is a list that should help you get your moth orchid to rebloom.

Why Won’t My Orchid Grow Flowers?

Light

  • The number 1 reason why your Phalaenopsis orchid isn’t blooming is light.  Moth orchids are considered among the lower light orchids, but they still need sufficient light to bloom.
  • I want you to walk over to your orchid and look at the color of the leaves.  Is it a deep, dark green?  If so, your plant probably isn’t getting enough light.  Move it to a brighter location.
  • I keep my Phalaenopsis orchids directly in front of Eastern-exposure windows.  The morning sun is OK, but just be careful not to expose your Phals to too much sun.  They prefer bright, indirect light.
  • You know that your moth orchid is on the high end of it’s light tolerance if you start to see that the edges of the leaves are reddish in color.  That’s OK, but your plant is warning you not to get any brighter.
  • There is one exception that I make when it comes to light.  When my moth orchid is in bloom, I move it to various areas in the house purely for display, even if I normally wouldn’t place it there for normal growth.  After the plant is done blooming (which could be months!), I’ll return the plant back to its window.

Watering

  • Go walk over and visit your orchid again.  How do the roots look?  Are they dry and shriveled up?  If so, you’re probably underwatering.  Some orchids such as cattleya have pseudobulbs which store water and this makes them more drought tolerant.  Moth orchids don’t have pseudobulbs to store water so you need to be more attentive to the watering.
  • Healthy orchid roots should be plump and look greenish, white or silver.  If they’re shriveled like your grandmother’s neck, or wrinkly but still firm, your plant needs more water.  If the roots are mushy and stringy, you’ve probably overwatered your orchid and caused the roots to rot.
  • PLEASE whatever you do, do NOT water your orchid with ice!  I don’t care what the label says. Moth orchids originate in the jungles of southeast Asia.  There are monkeys in those jungles.  Have you ever seen a monkey with a popsicle?  I think not.  So don’t give your orchids ice to water them. This is just asinine.
  • Don’t let your orchid pot dry out completely, if you can help it, but at the same time, don’t let your plant sit in water at any time.  Orchids need perfect drainage.  In nature, they grow on trees.  They are often exposed to rain and deliciously humid jungle air, but they have perfect drainage.  They’re never sitting in water.  If you slip your orchid into a decorative pot with no hole, that is fine.  Just make sure that when you water your plant, that it has fully drained into the sink before you slip it back into the decorative pot.  I do this all the time.

Fertilizing

  • When I ask people if they fertilize their orchid, I normally get a sheepish “no.”  Well, hell!  Every plant needs nutrients to survive, so go get some fertilizer!  I actually use an African Violet fertilizer (7-7-7) and I get great results with it.  I may experiment with various fertilizers in the future but this has given me great results.  Remember, plants can’t read your fertilizer label.  It’s our little secret.  You don’t have to tell them.
  • Whatever you do, please fertilize.  A good rule of thumb is “weekly, weakly.”  Moth orchids don’t need a ton of fertilizer, but a very dilute application weekly for most of the year except during the armpit of winter is in order!  If you let your plant get too dry, water it with plain water first, and then apply a solution of fertilizer.  This is so you don’t shock your plant.

Temperature

  • Moth orchids are tropical plants and need warm temperatures, so if you are comfortable in a room inside your house, your orchid probably is too.
  • If you have a stubborn orchid, something that often triggers bloom is a temperature gradient between day and night.  Often times, if you expose your plant to night temperatures that are 15F (or more) cooler at night versus the day, this may kick your orchid’s ass into bloom.  Just be sure to keep your plant above a minimum night-time temperature of around 50F or above.

A Summer Outdoors

  • Summering your orchid outdoors does miracles for your plant, whether it is an orchid or any other houseplant that you have.  I can’t emphasize this enough.  Just be sure to keep it protected from the sun and place it in a shady area.  If you live in an area with cold winters like I do, wait until the night time temperatures are consistently 50F (10C) or above before placing your orchid outside.  For my region of the Earth, this normally happens around mid-May or so, but I always keep my eye on the weather report and adjust accordingly.   Summer your plants outside whenever possible.  Let them reap the benefits of the air circulation, rainwater, and humidity.  Leave your orchid outside all summer until the night time temperatures threaten to go below 50F (10C) and bring your plant back inside at that time.  Some words of caution though if you summer your plants outdoors:
    • Make sure that your orchids are not sitting in water. If you have it slipped in a decorative pot with no drainage hole, you may need to remove it and place it into another pot with a drainage hole.  Otherwise, after a rainfall, you will constantly have to go and drain the pot.
    • Keep your plants in a protected area from the wind.  You don’t want your plants thrashed around and damaged.
    • Be especially careful when you first move your plant outside to keep it protected from any sun.  The intensity of the sun outside is different that the sun coming through your windows into your home.  Your plant will burn outside, so it needs a period of hardening off in complete shade.  Ideally, put it in complete shade, especially when you first bring them outdoors.

Other Resources

  • For more details on caring for your orchid, please read my other blog posts on Phalaenopsis orchid care.
    • Click HERE for my blog post on general care.
    • Click HERE for my blog post on what to do with your moth orchid when it is done blooming.
    • Click HERE for instructions on how to repot your moth orchid.