Are these grow lights close enough for my plants?

New leaves are encouraging, but they don’t show by themselves that the light is strong enough for compact growth. For high-light plants such as many cacti and caudiciforms, T8 bars may need to be quite close, and may still fall short depending on the fixture and how long they’re on.

Check the distance from the bars to the tops of the plants, not just whether the shelf looks bright. If you can, measure light at plant level. A proper meter is more useful than judging by appearance, while a phone app can offer only a rough comparison. Also check for stretching over time, since growth changes won’t be immediate.

I’d rearrange by light needs and height before buying more lights. Put plants with similar needs together, bring shorter ones closer to the bars, and give taller plants enough room so they aren’t right against the lights. A bright-looking corner can still leave plants too far away to get much usable light.

There isn’t one ideal distance for every plant in a mixed collection, so watch the new growth and adjust gradually. If stems start elongating or growth gets sparse, that spot may need more light.

Don’t assume every plant on the shelf is covered just because the bars span the shelf. Light intensity drops quickly with distance, and the fixture’s output and daily run time matter too. If the setup is for demanding succulents, verify the light at their leaves rather than relying on advertised specs alone.