I've grown a tomatoes for over a month in pots. I used normal non-sterilized soil. A few days ago, I added fertilizer, and bam, some fungi or mold started to appear on top of soil.

Is this actually dangerous for the plant or humans? Should I just put some more soil on top of it or maybe dig it up?

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1 Answer 1


Sanjihan this is simply fungus, probably grey mould...garden soils are full of spores, hyphae, seeds, bacteria...in the larger garden it is a balanced soil system. When you take out a little chunk to put in a pot you'll have no idea what you've got. Some kind of life that has checks and balances in the larger body of the garden will probably be free to explode with no controls in a pot. That kind of thing. Glad you got the soil down from the rim.

This mould is not a problem, that heavy soil is, grins. Just rake it with your fingers from time to time. Keep the lower leaves pruned up so no soil will splash up on the leaves. You'll want to change out the soil later. It would be a shame if there was ONE blight spore.

Tomatoes are supposed to be perennials. I have never grown tomatoes in the zones where that is possible. All I know is that by the end of our season, those tomatoes are so full of powdery mildew, dead leaves...we harvest the tomatoes and throw the plant into the compost pile. Are these determinate (bush) or indeterminate (vine)?

  • As always, thank you! This one is actually from different pot. I have 0 issues with watering:P This tomatoes are supposed to be indeterminate (based on variety), but the reseller of the seeds didnt actually specify that on the declaration. No one specifies that where I live. Pretty much no one I talked to didn't even know that tomatoes are perennials and that they don't have to die. The soil itself isn't heavy at all. These guys have loads of cori mixed in, so I hope that keeps it airy. You know me, I like my garden soil and I'll take my chanches :))
    – sanjihan
    May 5, 2017 at 17:49
  • No kidding sanjihan. You ARE a gardener and to you this experimenting is joy to you! Your questions are thought provoking, and that is why I even do this answer stuff. It is a scary responsibility to help those that are clueless and want success like now. Your questions FEED me! So thank you if that all makes any sense! Indeterminate means those tomatoes will take up less room and you'll be able to grow them vertically, training them on string attached to the ceiling?
    – stormy
    May 5, 2017 at 18:57
  • Well thanks. I'm getting questions on a regular basis so you wont be hungry:P yes, i hope my plants are indeterminate. But they wont be tall and stacked, because of pruning promoting lateral grow
    – sanjihan
    May 6, 2017 at 15:50
  • What do you mean by "just ONE blight spore would be ashame"? I think I have blight in my soil, (southern blight). It started out looking exactly like this, but then it started to grow all over my living green plant that was near the soil and now there are these tiny white-yellow dots/specks in the fuzz. Are the dots like spore-factories? Are these dots the mold anamorphing? And will these dots harm the plant??
    – Ginger
    Oct 19, 2020 at 19:39
  • Also will the mold harm the plant... if I leave it alone?? I'm so worried
    – Ginger
    Oct 19, 2020 at 19:39

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