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I make my own compost but wherever I use it lots of the previous years plants begin sprouting.
My veg bed this year is full of tiny mimulas, antirrhinum, foxglove and tomato/cucumbers. Is there a way to sterilize my compost to prevent this? I have enough trouble just with ever presant weeds.



The problem is that the c. heap doesn't heat up enough to kill the seeds. One solution is to not put the seed heads on the heap, especially those of foxgloves & alyssum, or any other prolific seeder. It's a pain cutting them off & composting the rest, but saves a lot of weeding. I don't know of a way to sterilise the compost, especially if you are putting it on your veg. plot. Someone else might know of a way though. At least you get plenty of plants for your ornamental garden, probably too many.

21 Jul, 2014


Your compost heap is not getting hot enough to kill off seeds - that requires a temperature of 130 degrees F for at least a week, and even then, tomato seeds may still be viable. This temperature is achievable using a hot composting method, but it requires regular turning and careful layering of materials. There is no other way of creating sterile, or at least seed and pathogen free, compost. Perhaps a change in how and what you compost might be useful - remove seed heads, flowerheads and fruits from green material before you add it to the compost heap. If your heap is not covered, cover it with something to try to exclude windblown seeds.

21 Jul, 2014


Ah, posted at the same time, sorry Feverfew!

21 Jul, 2014


My neighbour laughed when he saw me cutting seed heads off last year. He didn't now I'm the one laughing ;o))

21 Jul, 2014


As above, your heap does not get hot enough to kill the seeds. I also have this problem and so no longer spread the compost on the surface of the ground. Instead, I plan ahead and dig trenches where the different rows of veggies will go. I then put a layer of compost in the bottom of the trench and cover it over - not forgetting to mark the rows!

21 Jul, 2014


Good idea Bulba. I don't have a veggie plot , but I'm quite pleased with all the little Lobelia seeds that have come up everywhere & are now in bloom, helps fill in any gaps. Have thrown some Candytuft on the heap + seeds! don't mind where they come up.

22 Jul, 2014

How do I say thanks?

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