Reusing compost for vegetable growing!

Crawley, United Kingdom

Hi there,
I have a medium sized raised box which I filled with compost and manure last year and grew runner beans, peas, onions, carrots and parsnips. I'd like to reuse the compost for this years vegetables but am concerned as when I pulled up the carrots, they had tiny white worms coming out of them.
Am I okay to reuse the compost? Or should I do some sort of treatment to it first? I will need a few more bags of something to fill it back up to the top and would like to know if its best to use more manure or a certain type of compost.

Any help would be appreciated!

Thank you

San Antonio, TX(Zone 8b)

The worms were in your carrots or your compost? It seems they were in your carrots.... Can you put up a pic? Are you ManU fan? This is all horrible, sorry about your worms but try to get a pic. Did you use the UK cow manure that was really UK horse manure in disguise as the meat was? That may have a bearing on the situation..... Also ManU.

Crawley, United Kingdom

Hello. I'm not sure where the worms came from, but they were wriggling out of my carrots when I pulled them up! I can't put up a pic as it was last year so they're long gone now.
The manure was horse manure - it actually was what it said on the tin - for once! And no ManU. No football (or soccer whatever you want to call it). The manure didn't actually come in a tin... :)

Liberty Hill, TX(Zone 8a)

They are probably a carrot maggot or root worm. Not sure what you have in your area and I've never seen them but ive read about them. You might try googling and see if they look familiar.

Contra Costa County, CA(Zone 9b)

If you want to reuse the compost, but are afraid of whatever is in it, then you could put it through another composting treatment. Set it up for a hot compost:
Add some nitrogen (green matter, perhaps freshly mown lawn clippings).
Make sure it is slightly damp, not too wet.
Keep it in a fairly compact shape (such as a large cube), not all spread out.
Turn it often.
The idea is to get the inside really hot, hot enough to kill things. This will happen naturally with the composting process when it is set up right. Turn the compost so that all parts get a chance to be in the middle where it gets the hottest.

The pests may not live in the compost year round. Perhaps they are fly larvae or some other larvae, but the adult form flies or crawls away to live elsewhere. In this case, re-composting will not help.

If you can identify the pest, then you can research ways to control it. For example, if it is the larvae of a flying insect, then a fine mesh screen over the crop may exclude the adults, prevent them from laying eggs on your crop.

Ayrshire Scotland, United Kingdom

They are carrot fly larve, are a real pest, IF you have them then don't grow Carrots, Parsnips etc, in the same bed as the one that had the worms,

I would imagine the worms have gone by now as the winter would have killed them off if the birds never did, I try to keep the bed where the carrots are growing under horticultural fleece as this allows light in, rain to penetrate, keeps slugs and other veg eating bugs away, the covers need to be in place end of April as the carrot flies that lay the eggs to hatch are around May time, IFF you have to thin out your carrots, try NOT to break or disturb the soil around the little seedlings as it is the smaell of the carrot foliage that attracts the flies.
For this reason it is a good idea to grow onion or garlic along side the carrots as this distracts the flies in the first place. hope this helps you out.
By the way I hope you never composted the worm eaten carrots or you will just resycle the problem, the heat of the compost heap will MAYBE cause the whole cycle to be set off again.
Good luck, WeeNel.

Everett, WA(Zone 8a)

I would suggest not growing carrots there again for a few years. Unfortunately, if they are root maggots, there seem to be many crops that they attack. If they attack, they will also multiply on it.

"root maggots attack onions, carrots, cabbages, and other root crops."

You might Google "carrot maggots" and try to figure what crops are immune - then only grow those in that soil for 1-4 years.

Worse, an adult root maggot is a fly, so they may now be more widespread than they were. Perhaps ask local experts or nursery clerks "what can be done" after a crop of wormy carrots. They might have some relevant local tips like "keep the soil drier" or "lay down plastic film and cook them with solarization" or "plant parsley" or "they won't bother XYZ in this climate".

Do you usually have hard freezes but not last winter? Maybe (just guessing) long hard freezes will solve your problem for you.

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