Leggy Seed Sprouts (grow, tomato, northern, city)

[guidoLaMoto]

Many of us in more northern latitudes get a jump on MotherNature by starting seeds indoors this time of year. A common problem we face is getting tall, skinny shoots, stretching to get more light. The fix, obviously, is to give them more light. (may also be a watering problem.)


I've noticed that blowing on the sprouts periodically helps them grow thicker stems-- it's kinda like exercising to build muscles. The extra air flow also helps to avoid mold...You may be tempted to add a fan to the set-up, but that may thicken the stems but make smaller, stubbier leaves.


https://www.gardenbetty.com/leggy-se...-correct-them/


https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3257795/


As an aside, I've had a couple fluorescent fixtures with "grow bulbs" for the last few yrs, but wanted to increase my capacity this yr, so I got a couple cheapo LED shop lites….I've noticed that the tomato sprouts are leaning away from the grow lights and toward the LEDs. This may answer the question of "which is better?"

[luv4horses]

Seedlings are very sensitive to light but mostly because some colors actually slow growth. This allows the stem to thicken up. Generally white light has all colors but in different ratios depending on the source/ filament. That’s why some incandescent or fluorescent bulbs say “daylight”. LEDs also favor different wavelengths. So you will find that some of any type do better than others for what you want.

The effect is a combination of wavelength/color and intensity. And when the plant grows toward one source it actually means growth on that side of the stem is slower.