Grow Light for Justicia: Shrimp Plant Blooms Indoors
A grow light for justicia gives shrimp plant the steady light it needs to form its curved, shrimp like bracts indoors. UF/IFAS describes shrimp plant as a tropical perennial for full sun or part shade, while University of Missouri Extension explains how electric light fills the gap indoors.
The short answer
A grow light for justicia works well as a full spectrum LED hung 6 to 12 inches above the plant tips. University of Missouri Extension notes plants with no window light need 16 to 18 hours a day. University of Maryland Extension advises no more than 16 hours in total. Run the lamp on a timer.
How much light does shrimp plant need indoors?
UF/IFAS notes shrimp plant grows in full sun or part shade outdoors plus blooms year round in mild climates. Indoors, Maryland notes plants short on light turn leggy, fade in color plus flower less.
| Factor | Target | Why |
|---|---|---|
| Lamp height | 6 to 12 inches above tips | Intensity drops fast with distance, per Missouri |
| Hours with no window light | 16 to 18 | Missouri |
| Hours with some window light | 12 to 14 | Missouri |
| Upper limit | 16 hours | Maryland |
| Lamp type | LED | Red plus blue light, per Missouri |
Source: University of Missouri Extension plus University of Maryland Extension.
Where should a grow light sit for shrimp plant?
Missouri advises placing plant tips 6 to 12 inches from the light source, since intensity drops rapidly with distance. Hang the fixture so it can rise as the plant grows.
How many hours should the light run?
Missouri notes plants with no outdoor light need 16 to 18 hours a day, while 12 to 14 hours may do if some window light reaches them. Maryland advises no more than 16 hours in total.
How to: step by step
- Set shrimp plant in your sunniest window.
- Add a full spectrum LED above the plant.
- Hang the light 6 to 12 inches above the tips.
- Run the light on a timer for a steady day length.
- Watch new growth for new bract clusters.
- Adjust height or hours as the plant responds.
Troubleshooting
Long, weak stems: too little light. Maryland notes plants stretch toward light when it runs short. Lower the lamp or add hours.
Pale or brown leaves: Maryland notes too much light can turn leaves pale plus brown. Raise the lamp.
Few bracts: low light. Maryland links low light to diminished flowering. Move the lamp closer.
For lamp setup see grow lights for cannabis, led light distance cannabis plus grow light timers. Browse cannabis seeds. Kind Seed Co also stocks cannabis seeds.
Sources
- Shrimp plant, UF/IFAS Gardening Solutions
- Lighting for indoor plants, University of Maryland Extension
- Lighting indoor houseplants (G6515), University of Missouri Extension
FAQ
Can shrimp plant grow under a regular LED bulb?
A household LED gives some light, but a full spectrum grow light is brighter plus easier to aim. Missouri notes LEDs give red plus blue light. Hang the lamp 6 to 12 inches above the tips for the most useful light.
Should the grow light run all night?
No. Maryland advises no more than 16 hours of light in total each day. Missouri notes 16 to 18 hours suits plants with no window light, while 12 to 14 hours may do with some window light. A plug in timer gives the same day length every day.
Why is my shrimp plant not blooming indoors?
Low light is a common cause. Maryland notes plants short on light can turn leggy plus show diminished flowering. UF/IFAS notes shrimp plant blooms year round in mild climates when it gets full sun or part shade, so a grow light helps recreate that brightness indoors through winter.
How tall does shrimp plant grow?
UF/IFAS notes shrimp plant can reach two to six feet tall outdoors. Indoors it usually stays smaller in a container. Raise the grow light as the plant gains height so the tips stay 6 to 12 inches from the lamp, as Missouri advises for most plants.
Does window light count toward the total hours?
Yes. Missouri notes 12 to 14 hours of electric light may be enough when some window light reaches the plant, compared with 16 to 18 hours with no window light. Missouri also advises running the lamp at the same time as window light so the plant gets one long bright day.
