Kabochas are winter squashes of the Maxima species. Typically, they are left on the vine as long as the vine is alive. This is generally well into Fall but where you live might be earlier. Basically, you want the plant to throw every ounce of energy it has into its fruits before its life comes to an end.

Thanks tcstoehr!!

Hey I'm in Garland, so I'm your neighbor! When they stop growing and the skin turns harder, I'll pick them. I'm scared to leave them on the vine too long because something might attack them. I've had squash vine borers lay eggs on the squash and drill holes into them. That's why recently I've been covering up my squashes with some fabric mesh to help keep that from happening. Post pictures...

Some people use the thumbnail test. You press your thumbnail straight down into the skin and if it goes through then it's not ripe. If it resists like a plastic shell, then it's ripe. It takes some experience to get the hang of this method and judge it correctly.

Hi Christian! Yes, you are my neighbor!! :-) Woh, I probably need to get some tulle and tie them up in it.

Okay, here are some pics of the kabocha fruit in question.

I took pics of it at different directions so you can see it better I hope. So you see the skin on the top is turning grey/brownish. Tendrils? I think it's already brown, right? Or maybe not, I'm not sure which is considered it's tendril, is it the brown one or the green one?

What should I do?! Help!

I'd say not ripe. Consider the green juicy stem still delivering nutrients to this squash. Don't be in a hurry... these are WINTER squashes. Meant to ripen late in the season and not eaten until mid or late November. This is food to fill your belly through the lean mean winter months. These are not zucchinis for summer salads.

And yes, the tendrils are still green.

So it's okay to let it turn grey/brown completely on the vine?

I doubt they will turn grey or brown. Probably dark green depending on cultivar. When the vine is completely dead and withered away, the squashes themselves will be fine, as long as frost or animals haven't gotten to them... a real possibility. Consider the pumpkin fields in Fall with nothing but orange globes everywhere and no green leaves whatsoever. The general rule is to let the plant ripen its squashes as much as it possibly can. Another ripeness clue is if the stem has dried out indicating the the plant is no longer supplying the squash with anything. It does take time.

Not sure if you can see it, part of it is already grey, and the top is turning brown. Still okay to let it turn more grey and brown?

Update: the grey part has turned white. What do I do?

Can't tell without at least a picture. Turning brown offhand sounds like it's rotting inside. Is there any softness there or does the stem not feel solidly anchored? Any looseness in the stem is a very bad sign.

Dear NewTXGardener, those squash are no where near ripe yet. Relax and wait it out. You probably have two or three months to go yet.

No looseness in the stem, but the skin is turning color for sure. Last time I had this happen the whole fruit went bad when I left it on the vine, so that's why I'm asking. More pics below. I can bruise it with my thumb as you see below, but can't dent it much. Should I still leave it on the vine?

It definitely is not ripe or ready to harvest. The white/grey patch you see is just some surface mold and has nothing to do with ripeness. Just spritz it and wipe it off with peroxide or a 10% bleach solution to kill the mold before it penetrates the full skin. Once it does that the whole fruit rots. Mold often develops in shady moist parts of the garden so you have to be prepared to spot it and treat it. If you can turn it to get better sun exposure to that patch.

Otherwise just harvest it if you wish. It won't taste nearly as good as if it went till ripe and ready but no point in letting it rot either.

Dave

Oh okay, I guess that makes sense. Will wipe, but it won't wipe off since it's a part of the skin, it's not on the surface. That one gets direct sun actually, but it's been raining so it's been wet. Another one that's in shade (shaded by all the leaves up top) is very green and quite a bit bigger. So I initially thought it might be the sun exposure that caused the white/grey patch. Will see if wiping helps. Thank you Dave!

Just went out to wipe, it wasn't surface mold at all, it's a part of the skin turning grey/white, and the top part of the fruit is turning yellow/brown. It's going to rain soon, not sure if rain will make it worse.

Sorry I wasn't clear when I said wipe it "off". I didn't mean it would disappear. The point is to kill the mold with the peroxide or bleach. No the skin discoloration won't disappear but the mold will be killed.

Winter squash develop all sorts of skin discolorations as they grow and kabocha is no different. Google all the images of 'ripe kabocha' to see what I mean. But it is the stem and the adjacent tendril that tell when it is ready for harvest and based on your pics, this one has weeks to go. Without seeing it in person or holding and feeling it all we can go by is the pics.

But it seems you really, really, really want to pick that squash. ;-) It is your squash so pick it if it if you want. Just understand that winter squash aren't normally harvested until Fall as that is when they are at their peak so try to let the rest on the vine keep on going.

Dave

Yes, I really really wanted to pick it!! LOL! Okay, I will experiment and wait since I have at least one good one that can be my backup. :-D

No SVB that I can see, I looked at the whole vine, there's a part that's yellow, which is about 1 foot from this fruit itself (there's the stem coming out from the ground, and then the fruit, and then a foot from there is the yellow part of the vine) but it's also leaning against the trellis which might have bruised it?! I don't know. There doesn't appear to have any entry points for SVBs and I have not seen any SVBs in my yard. But I do have cucumber beetles. I didn't bring my phone with me when I went outside just now, but will later and will post a pic on that yellow part of the vine.

95% huminity, 91 F today, I feel like I'm in a sauna when I step outside! ;-)

OMG, OldDutch is right!! :~( :~( It looks like it's SVB! Here's the part of the branch that's yellow:

This is about a foot from the fruit, and then I went to the other side and saw this which is really bad:

Something is oozing out, it's still in there, should I cut it off so it won't hurt my fruit?? I don't have other fruits on the same vine, and the rest of this vine is on the trellis. Should I cut and take that @#$%^&* SVB out leaving the stem there or should I cut out the stem all together?

There's another one that has 2 parts of the vine like that too, and I looked, it looked like the surrounding nodes had rooted, so I cut off the yellow portions and found 2 holes (no more bug) with their poop oozing out and one with just poop oozing out and I stuck the tip of my hand trowel in and the worm juice hit me! Eew!!! So there was an SVB still in there, now it's dead.

AND, here's another one near the base of another kabocha vine:

There's a HOLE!!! And it didn't look like there was anything in there, I scraped everything out!!!

This one has a fruit hanging, and there's a node closer to the fruit with an emerging root, so I pushed more soil onto that node, hope it roots, should I cut the branch of this one out too?

What should I do with the greyish kabocha? Should I cut the infected part of the branch and kill the rest of that vine leaving just this fruit there? Or just cut and take out the SVB and leaving the branch hanging like that?

And on this one that has a hole at the base of the vine, should I wait for that node to root and cut out the branch? What do I do???

I cut out one SVB from the vine on the trellis, there was only one, shouldn't there be more? I made a pretty long cut and only found one. Since that part of the vine is on the trellis, I'm not sure how to put soil around it, so I pulled down another part of the vine closer to the soil, which is like 2 feet from the infected area and mound soil on it, hope it roots. So should I just let the greyish kabocha squash stay on the vine and hope that the SVB didn't already get to it?

The other vine with a hole at the base, I cut in more and saw an SVB!! Argh! I cut more and only saw that one, I thought there usually was more than one?! So on that one, there was already a node with an emerging root, I buried it more and packed soil on top, hope it will root. And then in a few days, I should probably cut it off from the base?

What else should I do??

Sorry for your SVB losses, we get them here in SC as well. I grow mostly moschata or butternut winter squash on trellis because they are largely unaffected by SVB. The solid stem pepo's like acorn, spaghetti and Tatume are not bothered very much by them either.

But we do have pickle worms that migrate here mid to late July, and they bore into the fruits. At that point you really have no choice but to harvest the squash, ripe or not.

Once inside you can either cut the worm out and eat it (unripe butternuts taste great, sliced and grilled or in casseroles or fried, pretty much any way that you like summer squash) or you can try submerging it and the worm may come out. If you want, then you can put it in a warm area of the house and cure it for 3-4 weeks. Mine kept fine for 6 months+ and still tasted great, just don't forget to cut out the worm eaten area! Never tried maxima' ripening off the vine, but it might work. The accepted wisdom for butternuts is the same as kabocha, allow it to ripen in the field, but sometimes you just can't get a harvest if you go by "accepted wisdom".

I have tried a lot of squash and cukes and all are affected by these destructive pests, ideally you get them in the ground early and harvest before the pickle worm gets here. We had a wet spring and I had to reseed, so mine won't be ready by late July. When they show up I am going to harvest mine, ready or not. They even bored into one that I put inside a ladies knee high hose!

Both SVB and pickle worms are deadly enemies of squash gardeners!

Pic to follow

Now that you know your problem is SVB you need to switch your focus
from that one squash - just do whatever you want to with it - and focus
on learning all about SVB.

In addition to all the info on the
web, there are literally hundreds of discussions about them here that
the search will pull up that should tell you more about them than you'd
ever need to know. Lots of good reading to do. ;-)

SVB discussions

Dave

Squash vine bores have seemed to follow me everywhere I gardened until I switched to the butternut/moschata group of squashes, which seem to be immune to SVB. In my current limited space I plant Butterbush, and have had them keep real well if properly cured. One lasted 18 months on the kitchen counter and was still good to eat, although finally starting to soften.

They are also pretty short season. My current crop is now just starting to come up, but should do alright if we do not get an extra early frost this fall.

OMG Mauldintiger, those are grossing me out!! :-D

Thank you guys for helping me diagnose this problem!! I had no idea since I'm new to gardening. I wonder if that was what happened the last 2 years my vines would just die and I never had any fruits to harvest.

So I found ANOTHER SVB this morning, on another vine, also in the middle of the vine, not at the base. But it was a side shoot and there was nothing there so I just cut the whole branch off. Luckily I saw it this morning, it's very close to the good kabocha and the biggest one I have this year.

Are they done laying eggs? Will I find more?

So now I'm wondering if I should harvest the grey kabocha...

Got another question for you guys. I see a few of my kabocha fruits have like a slit in the stem, like these:

Does that mean that the SVBs have gone in and the fruits are goners?

"Does that mean that the SVBs have gone in and the fruits are goners?"

No it just means that the stem has been damaged in some way - in one of many possible ways - and is browning and starting to die. It could be a simple split in the stem from inconsistent soil moisture or it could be nothing more than normal maturity of the fruit and stem. Since the bottom picture also shows some skin cracking and scarring I'd bet on the inconsistent soil moisture cause.

There is no signs of SVB frass and no SVB hole and even if there was an SVB in the stem it doesn't mean the fruit are "goners", just that they won't grow any larger.

Dave

Thanks Dave!!

Oh, the scaring of the bottom fruit is because when it was smaller, the skin was damaged by the surrounding thorny vines, it's windy here.

Sorry for your SVB loss. I took a big hit last year and grew more butternut this year as a result. I've been obsessive over my acorn and summer squash, but I can all but guarantee SVB will win in the end. I just hope to get some fruit first.

Hey NewTXGardener,

I would focus on checking my remaining vine for eggs, and removing the eggs. Also bury the remaining vines to encourage additional root formation. I have had very good success with Cindarella pumpkins (Rouge Vif d'Etampes), a C. Maxima variety like your Kabocha, here in the metroplex by planting them later in the summer from seed (like mid-August), covering the whole plants with tulle while young, then removing the tulle and burying the vines whenever possible. The vines will survive and even produce after they have been completely severed from the base of the plant because of the secondary rooting.