Cucurbits dying after transplant

Hello! I am a new gardener in Idaho. I’ve recently transplanted a bunch of my seedlings into the garden. Most of the plants are looking really good, except for my zucchini, squash, and cucumbers. Just a day or two after I put them in the ground they started to dry up, turn brown, and wilt. The pictures I’ve added are just the zucchini. The squash and cucumbers are in even worse shape. I’ve been reading up different cases of wilt but I’m not finding much that seems to apply to what I’m finding.
I’ve also just discovered that my beans look like they are beginning to decline as well. Could it be that the roots aren’t getting enough oxygen? If so, is there any way that I can help with that situation or are they doomed?

In comparison: pease, broccoli, mustard, kale, lettuce, beets, carrots, etc. all seem to be doing great.

Thank you in advance for any insights!

Hi Abigail!

I believe your plants are succumbing to a fungal infection, and based on the pictures provided I'm thinking it could be verticillium wilt or powdery mildew, or maybe a combination of both.

My cucumbers did the same thing! I was told that I put them out a bit too early- our night temps are still dropping into the lower 40s about half the time- and that cool temps encourage fungal infections, as James said.

I started another batch under lights, and maybe if I wait another couple of weeks I'll have better luck. Fingers crossed....

Thanks for the speedy response you two! Maybe I will try the same, replanting later on. So once the temps warm up these fungal issues won’t be as likely to happen? Is there anything else I can do to prevent it from happening again and should I be worried about it spreading to my other plants? I will also do my own research, thanks again for the insights!

Abigail Abts wrote: So once the temps warm up these fungal issues won’t be as likely to happen? Is there anything else I can do to prevent it from happening again and should I be worried about it spreading to my other plants?

Well, it depends. Warmer temperatures doesn't necessarily mean fungal infections decline. There are many variables, and damp/wet conditions favor the growth and spread of fungal infections even in hot sunny weather. Breezes can help keep things dry and aide in the slowing of fungal growth, but those same breezes will rapidly spread fungal spores to other plants. The best prevention is having healthy, microbially thriving soils, as those grow healthy plants which can resist infection from fungal pathogens. These fungal pathogens infect unhealthy and sick plants much more easily than healthy ones. Fungal pathogens are a part of natures decay process and clean up crew. As one of the methods of natural selection or "survival of the fittest", fungal infections like this help kill off weaker plants so the healthier ones survive.

Some avenues to consider are making compost and compost teas, applying these to soil and spraying the teas on plants. These good beneficial microbes make healthy soil, and also fight off plant diseases. There are mycorrhizal & bacterial soil inoculants that one can purchase to add good bacteria and fungi to a soil and help get the balance tilted in the right direction. I suggest avoiding chemical fertilizers, as they create all sorts of imbalance in soils and plants and can often do more harm than good. These are three examples of something that you can start right now and help nurture healthy plant growth the rest of this season.

I really have no idea, but is that a walnut shell I see in the first picture?  You aren't planting in close proximity to a black walnut tree are you?

A strong chamomile tea is a mild anti-fungal agent. When I had an outbreak of damping off on my indoor starts this season, I tried it out, and it worked amazingly well! My plants nearly all recovered, and the fungal thread disappeared within hours of spraying it on. I took a handful of dried chamomile blossoms and steeped them in boiling water for 20 minutes. Then just filtered it through a sieve and funnel into a spray bottle. A few squirts is all it takes. Your mileage may vary for outdoor fungals.

Good luck!!
Daniel

A strong chamomile tea is a mild anti-fungal agent.

Thanks, Daniel. I'll try that if I have any other problems. I've also used milk as a foliar spray for powdery mildew; it works like a charm for rhododendrons, but I'd be leery of trying it on seedlings, I think.

Does anyone know we (myself and the OP) should replant in the same spot? Would it be better to move the second planting of cucurbits, if possible?

Thank you James! I’ve got some compost going and a worm bin with some juice being collected under the drain, but I am a beginner to it all so who knows if I’m doing any of it right! We shall see. I will check out the inoculants for safe measure. Fingers crossed!

Michelle, there is one in relatively close proximity (about 30 feet or so), but it’s more that the garden is somewhat downhill from the tree so the nuts get all over. I have read about the issues black walnut trees can have on garden vegetables. My partner and I “inherited”/took over caring for the property and the garden was where it was when we got here, so we’re working with what we’ve got. But if you have information or tips I’d be glad to hear some.

I observe that squash and cucumbers do poorly if transplanted. If I set out transplants, and direct seed on the same day, the direct seeded plants will grow stronger and faster, and produce earlier,  and be more productive for the entire season.

I wouldn't be too eager to blame microbes for what seems to be a cultural problem of cucurbits responding poorly to being transplanted.

Abigail Abts wrote:
Michelle, there is one in relatively close proximity (about 30 feet or so), but it’s more that the garden is somewhat downhill from the tree so the nuts get all over. I have read about the issues black walnut trees can have on garden vegetables. My partner and I “inherited”/took over caring for the property and the garden was where it was when we got here, so we’re working with what we’ve got. But if you have information or tips I’d be glad to hear some.

I so understand working with what you've got.  The end of my grandmothers garden was at the edge of a black walnut canopy and she didn't seem to have many issues.  I have seen others try to plant right up to the base of them without success.  Ive heard it's just the roots that are the issue, but wonder if the shell husk has any ill effects?  I've never grown curcurbits from transplants before but I think the cool and wet weather we've been having might be the issue.  I was actually going to seed cucumbers and squash to transplant this week, but it's calling for cold temps over the weekend and I'll be moving seven flats of tomatoes and peppers inside so will be short on space.  I do hope you have enough seed to try again.  Looking forward to your progress.

if your garden is 30' downhill from a walnut tree that can be a big problem for just about any veg plants. I've always grown squash cukes, beans peas, pumpkins, seeded directly in the ground, stuff that needs warmer temps like tomato and peppers, eggplant do well transplanted after starting in greenhouse, cold frame or indoors or waiting till soil is at least 65 degrees

I agree a couple of pictures look like powdery mildew though I am not sure that there isn't some other things going on.

Any way you can make an easy solution for the powdery mildew with baking soda.

A really good treatment for powdery mildew is: 1 gal water, 1 T dish soap, 1 T baking soda.


This thread is for powdery mildew:

https://permies.com/t/139504/Powdery-Mildew#1093664

The last photo looks like cold damage, it looks exactly like mine if they get caught by frost. I can't help but notice that all the plants you say are doing well are cold hardy and those you say are sick like warmth.

yeah i would think it's pretty frosty in idaho still

Thanks everyone for the thoughts! So it may be that the soil is still too cold for the plants and that’s why some of them aren’t doing so well, is that what people are suggesting? I didn’t really think of that, but it makes sense! It’s been really warm here in this part of Idaho, ranging from high 60’s to 80’s so I started putting things in the ground, not really realizing the ground might not have warmed up yet.

A little update, some zucchini look like they’re doing pretty well, others not so much. I don’t think any of the squash made it, and whatever cucumbers are still alive I don’t think will be much longer. I will try direct seeding, thanks for the suggestion.

Hello everyone, I’m not sure if people are still visiting this thread but in case anyone does come around with similar issues I wanted to update. My zucchini are looking better than anything else in the garden at the moment. The weird transplant effects have been replaced by lots and lots of leafy greens and beets being chomped on.

I kind of just waited to see what would happen to them, not addressing any kind of possible fungus issue. So I think that those who mentioned transplanting issues/cold damage may have been right, because they’ve kind of just bounced back and are doing great. Like said, better than everything else I’ve planted.

No fungus issues! Yay!

Cucurbits do not like to be transplanted.  Direct seed them instead to avoid this pitfall.  It seems their root system cannot take even the gentlest disturbance, and transplanting usually is not very gentle.  The plants seem to do best if you wait until the soil is warm enough.