I'm planting in an indoor garden (with artificial lighting). This happens with some plants:

enter image description here

They "faint" and after some days dry out and die. This doesn't happens with some other plants but it happens with peppers, lettuce, arugula, basil. I don't think the trouble is the light nor nutrients in the soil (I have other plants in similar conditions thriving extremely well, mostly cucurbitaceae, tomatoes, beans, java plums, etc). Today I conjectured that it could be the heat. Do you have any idea why this happens?

  • Are you keeping the soil moist? Has it ever dried out completely? Commented Mar 31 at 3:56
  • Where did you get your soil? Commented Mar 31 at 3:59

3 Answers 3


That's Damping Off - A type f fungus disease that's killing them. You can look it up on the internet, and also there is about 7 different ways you can help avoid future dampening off. However, the bad news is, the plants that already have the disease, there is no hope for them. Clean your trays, pots and growers really well with a bleach formula or vinegar formula and then start again using very fresh soil and follow all the guidelines to prevent the Dampening Off Disease.

  • Be aware that there are multiple pathogens that can potentially cause damping off disease. Pythium is a popular one, but my hunch is it's not Pythium. Wilt diseases, like Verticillium can also cause it, I've read. Commented Mar 31 at 4:03

Nutrients should no be a problem: they are so tiny.

Light: stems are very long, so it seems some lack of light. Note: if you moves from a shadow place on a very sunny place, you may get them to burn (and ev. die). Do such changes gradually (e.g. one week in an intermediate place: light shadows, and some sun few hours per day).

Water could be an issue, but they do not seem over-watered or under-watered. But on your question you didn't mention water.

So I think the cause is the soil. On pots you should always use good topsoil. For seedlings it doesn't matter much the type, so usually there is one for them, with nearly no nutrients (it is just like a "sponge" to get support for roots and water). If you want to continue on pots, you shoul then place on some vegetable garden topsoil. But never use ground soil for pots. Soil is a living thing, pots will block most exchanges, so quickly the soil in pot could turn on very bad soil. [It is a common mistake all people do at beginning of gardening]. So for seed and seedling: either pot and bought topsoil (you may produce it, or sterilize it, but it is mostly inconvenient but for large parks), or put them directly on open field. Never mix your soil and pots.


Judging by the picture, I would guess that it is too little light. (white, very long stems usually indicate that)

What kind of lamp do you use? How far above the plants is it? How big is the area you are covering with it?

Heat can easily become a problem, how hot is it in the area where you grow your plants?

Also: You have a lot of seedlings coming out of the exact same spot in the pot. I usually grow my plants one seedling at a spot, so I have no experience if there can be too many of them. But it would seem logical, that having too many plants at the same spot might lead to problems too.

Edit: If light is not the issue, then maybe you have a funghi problem. Pythium, Botrytis and Fusarium all lead to damping off. 35° is very high and if I am not mistaken, the brazils have a high humidity too, both of these factors benefit the growth of funghi. (Frequently adding a little water and never letting the soil get dry does too btw)

  • I have various sources of light: One of them is a 400W metallic vapour lamp, 4x54W 5000K T5 lamps and one 105W 6500K lamps. They were under the 105W. With different heights according to the lamps power.
    – Red Banana
    Commented Mar 25, 2019 at 15:46
  • The temperature is from 30-35 degrees Celsius in the room (I live in a hot place: Recife, Brazil. 28° regresso usually).
    – Red Banana
    Commented Mar 25, 2019 at 15:49

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