Grow Lights for Bok Choy Indoors: Baby Plants
Grow lights for bok choy indoors produce tender baby plants when the room stays cool. UF/IFAS Extension notes bok choy grows well at 64°F to 68°F. Hang lights close above the leaves, run them on a timer plus harvest young plants before they bolt.
The short answer
Hang LED or fluorescent lights 6 to 12 inches above the foliage plus run them about 14 to 16 hours a day. Iowa State University Extension gives 14 hours plus University of Maryland Extension gives about 16 for greens. Grow at 64°F to 68°F, the range UF/IFAS gives, plus harvest young.
How much light does bok choy need indoors?
University of Maryland Extension notes that Asian greens grow acceptably well in less than ideal light plus that lights 6 to 12 inches above the foliage are typical. Iowa State University Extension places fluorescent fixtures 6 to 12 inches from the foliage plus LED 12 to 24 inches away in most cases.
| Stage | Light setup | Notes |
|---|---|---|
| Sowing | Cover the tray to hold warmth | Cabbage family seed sprouts in about 36 hours at 72°F |
| Baby greens | 6 to 12 inches above foliage, about 16 hours | Harvest at 4 to 6 inches tall |
| Larger plants | Fluorescent 6 to 12 inches or LED 12 to 24 inches away | 14 hours a day |
| Harvest | Cut at 10 to 15 leaves | Later plants turn a little bitter |
Source: University of Maryland Extension, Iowa State University Extension plus UF/IFAS Extension.
Why does bok choy bolt?
University of Minnesota Extension notes that if plants go through late spring frosts or more than a week of nights below 50°F, they are likely to bolt once warm weather returns. Bolting means producing a flowering stalk plus stopping growth. UF/IFAS gives 64°F to 68°F as the ideal range, though the crop tolerates 27°F to 95°F.
When should baby bok choy be harvested?
University of Minnesota Extension notes you can harvest bok choy a few leaves at a time plus that younger leaves continue to grow for later harvest. Dwarf varieties may be only six inches tall. UF/IFAS notes plants harvested with more than 15 leaves taste a little bitter, so cut at 10 to 15 leaves.
How to: step by step
- Sow seed one fourth to one half inch deep in cells or small pots.
- Cover the tray until sprouts appear.
- Hang lights 6 to 12 inches above the foliage.
- Run lights 14 to 16 hours a day on a timer.
- Run the room at 64°F to 68°F.
- Cut whole plants at the soil surface or pick outer leaves.
Troubleshooting
Plants bolt early: cold nights followed by warmth. Prevent a week of nights under 50°F.
Stretched loose plants: low light. Drop the lights.
Bitter leaves: harvest too late. Harvest at 10 to 15 leaves.
For related reading see grow lights for cannabis, led light distance cannabis plus grow light timers. Kind Seed Co also stocks seeds for indoor growers.
Sources
- Bok choy, an Asian leafy green vegetable emerging in Florida (HS1337), UF/IFAS Extension
- Growing Chinese cabbage plus bok choy in home gardens, University of Minnesota Extension
- How to set up supplemental lights for indoor plants, Iowa State University Extension
- Growing microgreens and baby greens indoors, University of Maryland Extension
FAQ
Can bok choy grow in a sunny window?
It can, but University of Maryland Extension notes window light may suffice only in some cases plus that greens generally grow better under grow lights. Iowa State University Extension notes nearly all indoor plants benefit from supplemental light during winter. Add a light on a timer to extend short winter days.
What size is baby bok choy?
University of Maryland Extension lists baby greens at 4 to 6 inches tall plus 21 to 40 days after sowing. University of Minnesota Extension notes dwarf bok choy varieties may be only six inches tall at harvest. Either size works indoors, so cut plants when they suit your kitchen plans.
Does bok choy regrow after cutting?
Picking leaves works better than cutting the whole plant. University of Minnesota Extension notes you can harvest bok choy a few leaves at a time plus that younger leaves continue to grow for later harvest. UF/IFAS notes home gardeners may take multiple harvests, picking plants at 10 to 15 leaves first.
Is bok choy a cabbage?
Yes. UF/IFAS describes bok choy as a Chinese cabbage variety in the cabbage family, Brassicaceae. University of Minnesota Extension notes bok choy, also called pak choi, grows an upright clump of dark green leaves with thick white or light green stalks rather than forming a round head.
What temperature suits indoor bok choy?
UF/IFAS Extension gives 64°F to 68°F as the ideal range plus notes the crop can tolerate 27°F to 95°F. University of Minnesota Extension notes more than a week of nights below 50°F can trigger bolting once warmth returns. A cool room near the ideal range suits plants under lights.
