On 09/03/2021 22:26, Gary Woods wrote:
On Tue, 9 Mar 2021 21:59:31 +0000, Jeff Layman
wrote:

Have you got anything else growing in that compost? I'm wondering if it
has been contaminated with lows levels of a herbicide like aminopyralid.

I mostly use "Pro Mix," U.S./Canadian product. Pretty much everything
else does fine in it, under the same light. Tomatos, Leeks, Tuberous
Begonia cuttings and seedlings. The light I'm using has a number of
colors in series string, including IR. Look up "Vipar Spectra;"
Chinese made so probably widely available, perhaps under various
names.

I first played around with with "Grow-lamps" around 40 years ago (240W
MBT), and later with a 13W fluorescent. That's my total experience, so I
never used leds. Reading some articles suggests there's been quite an
improvement, but there's maybe a way to go. FWIW I don't remember
getting leaf damage with the very inefficient MBT lamp (which produced a
lot of heat), but it was a long time ago!

I see there are some reports of leaf damage due to overheating (see Myth
#14 at https://www.gardenmyths.com/18-led-grow-light-myths/), but that
doesn't sound like your problem. There's some discussion here as to
whether it's due to heat or something else:
https://growdiaries.com/grow-questions/538-does-the-leaf-curling-mean-lights-are-too-close


If you've still got some basil seeds from the same packet and the same
batch/bag of compost it would be of interest to try a comparison of
led-assisted and non led-assisted growth to see what happens.

--

Jeff