Hi ditnc,

I'm sorry to hear about the loss of your zucchini plant. Luckily, I haven't had any problems with SVBs yet (knock on wood). I would suggest you use new potting soil for your new plants for 2 reasons:

1) You definitely don't want any SVB larvae that may be hiding in the old potting soil to emerge and attack the new plants.

2) I never like to plant using "used" potting soil. You want to start the new guy with a potting soil that still has its zeal.

Potting soil is relatively inexpensive and well worth the investment. You can even make your own potting soil, if you have the time.

I hope this is helpful, and good luck with your new zucchini plants.

Tee

Here is a link that might be useful: Making your own potting soil

I wouldn't reuse it for the reasons listed above. Depending on how large the plant was to begin with, I bet you'll have a hard time dividing any useable soil from the root ball anyway.

Mine were destroyed last week by SVB. You have my condolences.

Any borers that may be in the soil will be ones that already dropped off the plant and will already be pupating. They will emerge as moths next spring, not as borers.

New moths may find the new plants and lay more eggs but honestly SVB in container plants is rare and unusual unless the containers are out-and-about in a garden area rather than say on a deck or patio.

Once you read about the life cycle of the SVB at the link below I think you'll see why re-using the potting soil is fine. If it makes you feel safer you can sift the top 6 inches of the soil and remove any pupae you may find.

Dave

Here is a link that might be useful: Life Cycle of the Squash Vine Borer

Thanks all and appreciate the link Dave. They really were SVB larvae, identical to the pictures and tons of frass. I wonder what a pupa looks like - I can't really tell from the pics in the link.

Anyway, I already replanted yellow squash seedlings and zuke seeds in new mix before reading Dave's post. It may be too late to try again, but it stays warm here until October at least with no frost until November so it can't hurt!

I just posted a reply to someone else's post about SVBs ("the AUDACITY") asking if there is a date by which the moths go away. But then I just read an article that said the south may have 2 generations per year. If anyone has knowledge about this, would appreciate.

Thanks again for the replies. I need squash! :-)

I lost my straightneck squashes to SVB last month :-(in an Earthbox) and after mourning the loss decided to try planting Diva cukes in the same place. Felt fine with this for the reasons Dave mentioned, and so far so good! This time around I am armed with some BT, and re-planted some squash in other containers. Pattypans have blossoms but the others are a couple of weeks behind...maybe I will have squash in August!

SVB pupae are 3/4 to 1" long dark brown lumps that look like clumps of soil made from paper mache and are the shape of the last digit of your little finger. Or, if you'll forgive the analogy, small dried puppy turds. ;)

Dave

We have a warm and long enough summer that we get two generations a year which sucks. If I start my seeds indoors in late March and put them out right after the last frost, I can get plenty of veggies before the SVB hit in June when they're manageable, but come July, they destroy everything no matter how hard you try to keep those eggs off.

I second the tumble turd statement.

Can I plant chard or cauliflower in the soil where my SVB destroyed zucchini and squash were?

Maybe if the SVBs could find some squash in your chard or cauliflower, it might be a problem. SVBs attack vining crops - squash, pumpkins, more rarely melons and cukes. But look out for those chard and cauliflower vine borers (CVBs)!