Can unsterilized compost ever be used for tomatoes?

Hi there,
In future I will use sterilized compost to germinate seed, but wondered if my compost can ever be used for tomatoes if left untreated (when transplanting)? It was well broken down (crumbly and earthy smelling) and I don't reuse tomato soil from previous plants, in case of disease. My courgettes, cucumbers and raised beds don't seem to object to my compost. Should I just stick to shop bought compost for toms?

(Bit of background...I'm new to forums) I have grown tomatoes and various other veg for a few years now with few problems. I normally buy grow bags but finally had a decent quantity of what I thought was good home made compost. This year, germination didn't start well on anything, but I think I've learned from that and finally got some results. It was a while ago now, what with a late start and prolonged cold/wet weather, but I think I might have tried germinating my seeds with my homemade (unsterilized) compost, not knowing that this is not recommended.

After germinating indoors, my veg plants (tomatoes, courgettes and cucumbers) have been in my shed, by a little window, waiting until I can harden off/plant out. All looked well (lots of green healthy lookng leaves and a few flowers starting) but I noticed this week that nearly all the tomato stems are brown/ some slightly deformed (tough and woody) for an inch from the soil. I have disposed of them assuming they're diseased, which is very disheartening after finally getting them started off. I have little other use for compost other than raised beds and a few house plants.

Thanks in advance.



  • figratfigrat Posts: 1,619
    Not much help now, but if the rest of the growth on the toms looked healthy I wouldn't have junked them. I do use bought compost for germination and potting on, but have successfully grown toms in containers with home made potting compost and leaf mould mixed into bought compost. And I always get zillions of tomato seedlings coming up in the garden when I've put my home made compost on the beds. They go back in the compost bin to return to the garden albeit in a different form....
  • sotongeoffsotongeoff Posts: 9,806

    You should always use a sterilised compost to start seeds off-anything else is just asking for trouble.

    As regards garden compost-you have no idea of the nutrition content and I only use that as a soil conditioner-not for growing plants-again you have no idea that all pests, diseases,weeds seeds etc are not still present.

    To me it is false economy not to buy propriety compost for plants-everything costs money that I would rather spend it on that than lose plants.

    That is my take on it -others may be of a different opinion

  • Hi Figrat,

    Blimey these replies were quick

    I also see lots of tomato seeds sprouting when I use the compost for anything else.
    I might be able to salvage the plants (I put them in my brown recycling bin last night, so they're on the top and probably fine).
    I have been scouring the net looking for help and mostly found very negative results about spreading disease, hence my panic. I didn't want to plant them out and contaminate anything further.

  • Hi Sotongeoff,

    As I say, I will use sterilized compost in the future. Still learning I guess. I know what you mean about a false economy, wasn't so much trying to save money as put my compost to good use.

  • figratfigrat Posts: 1,619
    Apparently you can sterilise home made compost in the microwave. But I think it's a bit of a smelly process.
  • ItalophileItalophile Posts: 1,647

    Apart from the various possible nasties in home compost, you'd have no idea what the pH might be.

  • BerghillBerghill Posts: 2,823

    We grow our toms in the soil to which we add copious amounts of our own compost. Alright the plants are put in bought compost in bottomless pots, but the roots go down into the soil. They seem to thrive.

  • ItalophileItalophile Posts: 1,647

    Home compost is fine once the plants are established. I use tons of it. Sowing seeds in home compost is the problematic one.

  • I use home made compost as a dressing in the garden and mix it with shop compost for my tubs. I haven't had any disasters but have had lots of suprises popping up everywhere ! Usually tomatoes and sweetpeas.

    Not a bad thing really !



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