Orchid Care 101: Light, Water, Soil, and Food
Quick answer
Get the light right, water thoroughly but rarely, use a bark-based mix instead of potting soil, and feed lightly. The number one killer of houseplant orchids is overwatering combined with the wrong substrate, and fixing that makes most other problems disappear.
If you bought your orchid potted in soil, repot it into bark as soon as the current bloom finishes. That single change prevents the majority of orchid deaths.
Light: read the leaves
You do not need a light meter. The plant reports its own status through leaf colour.
- Just right. Medium green with a slight yellowish cast. This is what a well-lit, blooming-capable orchid looks like.
- Too little. Very dark green leaves and healthy growth but no flowers. Move it closer to the window.
- Too much. Red or purple patches, or bleached white spots. Pull it back from the glass or add a sheer curtain.
For Phalaenopsis, an east or west window with no direct midday sun is ideal. South-facing works behind a sheer curtain. North-facing is too dim to bloom.
Water: drench, then leave it
Forget the ice cube trick. In the wild an orchid is drenched by tropical rain and then dries out in moving air. That is the pattern to copy: every one to two weeks in a bark mix, depending on the plant and your conditions.
Underwatering is recoverable. Overwatering usually is not.
Because bark drains so fast, the real challenge is making the water actually soak the mix rather than channelling straight through it. Two methods, and you want both.
Top watering — every time
- Take the orchid, still in its grow pot, to the sink.
- Pour water on until it pools on top before soaking in, tilting the pot to spread it. Keep going until it runs freely from the bottom.
- Drain completely. Never leave the pot standing in water.
Bottom watering — every fourth to sixth watering
- Stand the pot in a bowl with an inch or two of water.
- Leave it 30 to 60 minutes. Water wicks up through the drainage hole and fully rehydrates bark that top watering skims past.
- Lift it out and drain. This one also encourages roots to grow downward.
How to know it is time: push a finger into the bark. Even slightly damp means wait. Completely dry means water. In a clear pot the roots tell you outright — green is hydrated, silvery grey is thirsty.
Substrate: where most orchids are lost
Orchid roots need air. They evolved on tree bark, not in ground. A lot of what is sold as “orchid soil” in big-box garden centres is too fine, too peat-heavy, or full of components that compact and trap moisture.
What you actually want: chunky bark between about 5 and 15 mm, perlite or mineral grit for drainage, and biochar to buffer the impurities in tap water. Minimal peat, no compost, no soil ingredients of any kind.
Built to this spec — Molly’s Orchid Mix: coarse pine bark, coco chips, biochar and mineral grit, pre-rinsed and screened. If you would rather build your own, start with medium-grade orchid bark plus perlite and biochar.
Replace the mix every 12 to 18 months, ideally straight after a bloom cycle, or sooner if the bark has gone soft, the pot smells musty, or water stops draining through.
Food: the mix is not the fertiliser
A potting mix is structural, not nutritional. Molly’s mixes carry no added fertiliser by design, and the trace nutrition released as the components slowly break down is not a substitute for feeding.
Orchids are light feeders, and over-fertilising burns roots far faster than under-fertilising slows growth.
| What to use | A balanced orchid-specific feed, around 20-20-20. Generic houseplant fertiliser is too strong. |
| How often | Weakly, weekly. Quarter strength every week during growth, then skip two or three weeks every couple of months to flush salts. |
| How to apply | Mixed into your watering routine, skipping every fourth watering and using plain water to flush the pot. |
| When to stop | Through dormancy, which for most orchids runs October to February. |
What the symptoms mean
| Symptom | Likely cause and fix |
|---|---|
| Yellow leaves | Overwatering, or bark that has decomposed. Check the roots. Mushy means rot, so repot immediately. |
| Wrinkled leaves | Dehydration or root damage. Healthy roots means water more often. Mushy roots means the plant cannot drink and is rotting. |
| No blooms | Usually too little light, or no night-time temperature drop. Aim for 10 to 15°F cooler at night. |
| Roots escaping the pot | Entirely normal. Aerial roots absorb humidity from the air. Do not bury them. |
| Brown spotting on leaves | Fungal or bacterial. Improve air circulation and keep the leaves dry when you water. |
Common questions
How do I get my orchid to rebloom?
Two things trigger it: enough light, which is usually the limiting factor, and a night-time temperature drop of 10 to 15°F. Moving the plant nearer a window often delivers both at once.
How often should I water an orchid?
Every one to two weeks in a bark mix. Technique matters more than the interval: drench until it runs out the bottom, drain completely, then wait until the bark is dry before the next one.
Should I cut the flower spike after blooming?
For Phalaenopsis, cut just above a node partway down and the plant will often branch and rebloom from it. If the spike has gone brown and dry, cut it back to the base instead.
Do orchids need special fertiliser?
A balanced orchid feed around 20-20-20 at quarter strength is ideal. Generic houseplant fertiliser is too concentrated and burns the roots. Feed weakly and weekly, and flush with plain water every few weeks.
Get the substrate right first
Coarse bark, coco chips, biochar and mineral grit — pre-rinsed and screened for epiphyte roots.
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Keep reading: Do orchids need soil? · How to repot an orchid · 15 types of orchid worth knowing
