I'm sorry, but I don't know what caused that split.

I'm posting because I'm simply so amazed that you've managed to grow a squash that large in a pot that small.

I would be 99% certain that any attempt to transplant it would kill it, but since it shouldn't exist as it is now in the first place I could be completely wrong.

Your squash plant is fine. While the split is not ideal it won't kill the plant and it is not the fault of any pest. In the future you can try planting the squash up to their seed leaves if you are transplanting, otherwise you could mound a little soil around the stem below the seed leaves. These compact plants have no tendrils like most squash and cannot secure themselves to anything. So when a big gust of wind comes it moves the plant all around. The stress on the stem is what causes the split. I would be willing to wager that those sticks are a recent addition and there was no support before, correct? If you have a small garden with few squash plants like this I would say give them some support, but it really isn't necessary. And the other poster is right in saying that transplanting now would be very bad for the plant. Just keep it watered and you will have plenty of fruit.

Thank you so much for your responses! I'm very glad my plants are ok!
The sticks were placed when I transplanted it as a seedling and offered support in the beginning but they've gotten loose and I've had to push them around as the stems and flower buds grew. Right now it doesn't look like they're doing much. And you're right about the wind, the plant moves in the breeze, this started once the plant got bigger.
I think I was getting a bit confused as it was growing because like you said, this type does not have tendrils to attach itself to anything. I think that's what I was waiting to see, from what I've read. I have actually never seen a squash plant before so this has been very interesting for me.
I really appreciate your help!!!
And, Iam3killerbs, I too am amazed at how big this plant got in this tiny container! I found the containers at the 99cent store and they have little feet and 3 drain holes so I bought several. I ran out of big pots and thought, what the heck...lets just see! lol

I agree with the others.
That is one nice squash plant.
My husband and I grow 2 acres of pumpkins and squash each year. Stem split is common and usually is due to extreme temperatures changes and uneven watering. Last year we had some really hot days and cool nights and also heavy rains...the little squash stems couldn't take the heavy doses of rainwater surging thru and so they split.
One thing you can do is take some potting soil and mound it around the stem and build it up around the split. That will stabilize your plant a little and also keep that split from drying out as quickly.

I was going to post a question about this on my watermelon plant. It started to show a split like this yesterday but it's been growing really well. I'll just keep a close eye on it I guess.

Hi agngg, how are those plants doing now? It is a beautiful squash plant? It looks just like the Magda I am trying to grow.

Right about the time of your first post I had some baby plants in the ground which showed splits in the main stem just like yours. I was relieved to hear it would not be a problem. My plants did not die but they have not done well either. The ones with the bigger splits wilt pathetically within minutes of strong sunshine suggesting that the stems cannot deliver enough water to the leaves from the roots. And all the plants seem quite small for the type from the descriptions in the catalogs again suggesting not enogh nutrition is reaching the upper parts. I don't think the soil is a problem because the two or three plants that did not split are doing substantially better.

An update would be nice.

Hi weirdtev, we meet again here. Are you saying that it is possible to transplant squash seedlings and plant them deeper than the soil line in the pots, up to their seed leaves? Wouldn't this rot the stem? I would be glad to have some reassurance on this as my new seedlings are somewhat leggy.

Thanks, K.

Hello!! The squash plant has survived! ;) Thanks for asking!
The two plants that split were in ridiculously small containers,
And after the first 4 squash ripened on each plant, the new center leaves
started coming out way smaller and of course all the roots towards the soil surface. I ended up replanting both plants in a baby tub I had lying around.
Not the best home, but they are still producing!
I also have another in a 10 gallon pot that is doing beautifully with no splits in
the stem. The other 2 are not as beautiful as they once were but they have given me several lovely squash so I don't mind!! Not bad for my little experiment!!
Thanks again for asking and I hope your plants keep thriving!!
Also when I replanted, I brought the soil up a little higher and mounded it around the split and it helped stabilize it a little, it didn't hurt it at all.
Good luck and keep us posted!!

My bush Zucchini(s) also have a split main stem. Maybe this is normal for squash? The splits don't seem to be having any ill effects on the plants, and most of the stems seem to be healing. Don't see any evidence of SVB, and I think it may be too early for them to be active this early in the season here in 6a.

I have a few young squash plants recently planted in a raised bed. Its been windy for a couple of days and excessively so today. Yesterday I noticed stems with white bruises and today found the bruised areas split open. No bugs or vine bore evidence. I am certain the splits are from the windy conditions. Today I mounded good earth about the split stems. Squash plants' stems will put down roots in locations where the stems rest on the ground or are partially cover with earth. Hopefully the plants will continue with healthy growth.