This summer I started an indoor herb garden, but something is killing nearly all my plants, which I am growing in pots under a fluorescent grow light. It started with my basil and has spread to my mint, sage, and thyme, and is possibly starting on everything else except my chives. Earlier, I had an aphid infestation in my basil (which I just realized today has come back), and I treated with an oil/soap spray, which seemed to pretty much get rid of them. When some of the leaves of started dying later, I thought it was because I had put the plants back under the light too soon after the spraying and they got scorched, but today I saw it on the plants that had never been sprayed. Parts of the leaves are getting crispy, losing their green and getting tiny black spots, then turning brown under the spots and dying. The earliest plants to succumb have already lost all their leaves. I think it may be too late to save this year's garden, but I've been trying to figure out what's going on so I can avoid it next time. I haven't found any pictures or descriptions that quite match up to what I'm seeing, so I'm attaching a picture of my sage seedlings. I hope someone can help. Thanks!
I suspect you'd do better growing them outdoors. Water only when the soil is dryish; don't over-water, the soil should never be soggy. With small seedlings like this, far safer to rub off aphids by hand, rather than blasting them with chemicals.
Thanks for your advice. I'm definitely a novice here. Unfortunately, my choices are indoors or not at all, given where I live, and I did hope I'd be able to have some fresh herbs on hand for my kitchen. So you think it's overwatering? I'll try to be more careful about that, though I didn't think I had been watering too much. I may have overcorrected because the only plants I'm used to caring for need even less watering. Do you think that there is an infection involved that could be caused or exacerbated by overwatering or just that dampness itself is causing what I see? Basically, should I treat the affected plants as though they're contagious? As for the spray, it may have contributed but can't be the only cause since I never sprayed the seedlings. But for the future, I'll be careful with them.
