Grow Light for Verbena Seedlings: Sunny Starts
A grow light for verbena seedlings gives these sun loving plants a sturdy start during their weeks indoors. NC State Extension lists verbena for full sun, with 6 or more hours of direct light a day. Sow in early spring, hang lamps close plus run them most of the day.
The short answer
Start verbena indoors about 10 to 11 weeks before planting out, as University of Minnesota Extension suggests. Hang fluorescent or LED lights a few inches above the seedlings plus run them about 16 hours a day. Harden plants off, then set them in full sun after frost.
When should verbena be sown?
Early spring. University of Minnesota Extension lists verbena among the flowers sown in early March, with 10 to 11 weeks indoors. That is a long stay, so seedlings depend on the lamp for most of their light.
Illinois Extension notes that without enough light, plants become leggy. It explains that leggy means stretched stem sections between the leaves, caused by absent or low light.
| Stage | Light distance | Daily hours |
|---|---|---|
| Seedlings indoors | A few inches above tops | 16 hours, 18 at most |
| Garden planting | Full sun | 6 or more hours of direct sun |
Source: Illinois Extension plus NC State Extension.
How close should lights hang?
Very close. University of Maryland Extension advises lights no more than 4 inches above the seedling tops, with 2 inches as ideal. Illinois Extension notes that fluorescent tubes give off so little heat that they can sit only a few inches from the plants.
Raise the fixture as the plants grow so the gap stays the same.
How long should lights run?
About 16 hours. Illinois Extension uses an automatic timer for 16 hours of light per day, with 18 hours as the maximum for seedlings. University of Maryland Extension suggests 12 to 16 hours daily.
A timer makes the routine simple plus spares daily switching.
How to: step by step
- Begin seeds inside in early March for 10 to 11 weeks under lights.
- Water until the mix is evenly moist, not wet.
- Suspend lamps 2 to 4 inches over the seedlings.
- Set a timer for about 16 hours of light daily.
- Repot seedlings as they grow.
- Acclimate plants before planting in full sun.
Troubleshooting
Leggy stems: weak light. Lower the lamp to a few inches above the tops.
Seedlings collapsing at the soil line: damping off. University of Minnesota Extension notes that bottom heat can help prevent this death of tiny seedlings, so warm the mix plus water less often.
Plants spreading where unwanted: volunteer seedlings. NC State Extension notes that tall verbena spreads by seed, so do not let it spread into natural areas.
For related reading see cannabis seedling light schedule, leggy cannabis seedlings plus hardening off cannabis seedlings. Kind Seed Co also stocks cannabis seeds.
Sources
- Verbena bonariensis, NC State Extension Plant Toolbox
- Glandularia canadensis, NC State Extension Plant Toolbox
- Grow lights for starting seeds indoors, University of Maryland Extension
- Supplemental lighting for indoor seed starting, Illinois Extension
- Starting seeds indoors, University of Minnesota Extension
FAQ
How long does verbena stay indoors?
University of Minnesota Extension lists verbena among the flowers sown in early March, with about 10 to 11 weeks indoors before planting out. That timing gives seedlings a long stretch under lights, so a close lamp plus a steady daily schedule matter more than for quick crops.
Can verbena be direct sown?
Verbena does grow from seed. NC State Extension lists seed as a recommended way to grow rose verbena. It also notes that both tall verbena plus rose verbena will self seed in the right conditions. Indoor starts simply give plants a head start before the season warms.
Does verbena need full sun?
Yes. NC State Extension lists full sun, meaning 6 or more hours of direct light a day, for both tall verbena plus rose verbena. Both also tolerate partial shade. Rose verbena wants well drained soil plus handles drought once established, so a sunny dry bed suits it.
When should verbena be planted out?
After frost. NC State Extension notes that tall verbena is a tender perennial hardy in zones 7 to 11 plus is grown as an annual in cooler climates. Harden seedlings off first, since plants raised under lights have not faced full sun, wind or shifting temperatures.
Is verbena a perennial?
It depends on the type plus the climate. NC State Extension describes rose verbena as a short lived perennial that is often grown as an annual in the north. Tall verbena is hardy from zones 7 to 11 plus is grown as an annual elsewhere.
