Growing Pumpkins with Cardboard and Compost

Growing Pumpkins with Cardboard and Compost

There’s something really wonderful about the idea of pumpkin patch, sort of like a fairy tale, with those big lush leaves creeping and sprawling all over the place and the wonderfully eccentric fruits hidden amongst it all, like treasures waiting to be discovered. Well, today’s the day to make those dreams come true as I convert this area of lawn into a home for hulking great winter squash and pumpkin plants. I’ve got everything I need and I’m raring to go. Let’s do it!

Do you ever feel like you’ve bitten off more than you can chew? I wanted to fit them up here, but what the problem is: I just don’t have any spare bed space. This is the only bed that’s empty, but my sweet corn is destined to go in here in two weeks. I’ve just planted this bed here with more asparagus, and here I’ve got my Jerusalem artichokes, or sunchokes, which are beginning to push through. Truth is, I’ve gotten a bit carried away planting new crops and have simply run out of space. So I’ve opted for a new growing area down here, and I’ve got a hunch it’s going to be an absolute winner.

Squashes and pumpkins love it warm, sunny, and the soil nice and moist ideally, and this area here is perfect for that. It faces the afternoon sun—bit cloudy today, though—and it’s in a sunken position, so it’s nice and sheltered, all backed by this stone wall which will absorb the heat during the day and then emit it at night to further warm this area nicely. The soil here gets really saturated in winter, but that’s actually great for our drier summers because it’ll hold on to moisture for longer, and the area is going to be covered with a bit more compost and manure anyhow to aid with drainage. The soil hasn’t been dug before, and I cut the grass here very infrequently, so the soil itself is going to be full of organic matter courtesy of all the grass roots. This really is the ideal spot.

The first job is to prepare the ground, but I’m not going to dig it—that’s far too much like hard work. Instead, I’m just going to smother the ground with cardboard. This area just comprises grass and a few nettles as well, which are both easy to control. I prepared the ground by mowing it as close as I can, letting everything drop where it falls. This will weaken the grass and nettles and provide a nice, kind of level surface on which to lay our cardboard. Now if you have more pernicious weeds with deeper tap roots, say like docks or brambles, do what you can to dig those out because they might well survive and pop through.

Right, the first thing to do to prepare our cardboard is just to remove any staples or bits of tape like this. We just want to be left with nice, clean, plain cardboard. Perfect. And now I’m just going to open it all out and cover this area with the cardboard, and because I’ve got a nice stash of it, I’m going to do a double layer just to be sure.

Now if you’re just using one layer, do make sure you overlap your cardboard nice and thickly so that the weeds can’t grow up through the gaps. But with this double layer, well, I don’t really need to worry about that. They’re really kind of smothering that grass. I’m extending it out to this side only. I’m not going any further because there’s this kind of like ant hill here, and we’ve got green woodpeckers in the garden, and they love this. This is kind of like a banquet for them, so I’m not going to disturb that. They can carry on pecking away for ants there.

That’s all laid down. Now this will rot down over the course of the summer, by which time the grass and nettles underneath should have died. I’m just finishing off this cardboard layer with a bit of a watering here just to soften it up, ready for the next layer which will be our manure layer.

Right, that’s the last of our magical muck spread out. This will help to bury those nettles and grass a little bit deeper and, of course, give something for our squashes and pumpkins to root into and power all of that luxuriant growth. Now I’ve got three different types of pumpkin and squash to plant today, and I’m so excited to get them into the ground at last. Let me show what I’ve got.

First up is this: it’s Tonda Padana, which is a dumpling squash. This has got beautiful, magnificent green strips with raised, orange ribs to it, and when you cut it open, a deep orange flesh that is beautiful roasted or in soups, and apparently made into gnocchi. Could we be gnocchi on Heaven’s Door with this one? I hope so.

rowing Pumpkins with Cardboard and Compost -Pumpkin

Then over in front of me here, we’ve got three butternut squashes. Now I’ve chosen a variety called Hunter. It’s a hybrid, and it’s been bred to cope with our leaden skies and decidedly iffy climate. And then behind me here, I’ve got some classic pumpkins. This one is called Harvest Moon, I think. Now this produces just standard but beautiful pumpkins, suitable for carving and, again, with a lovely sweet nutty orange flesh that will be great in soups or roasted too. I love a pumpkin that is multi-purpose, both decorative and delicious—that’s the way to do it.

If you’ve not sown your squashes or pumpkins yet, there’s still plenty of time. Now I like to sow them into pots or plug trays away from the growing areas and the birds and slugs. Then once they’re a bit bigger, that’s when I plant them out. Now to sow them, I just nick the seed coat ever so slightly with some nail clippers. That helps the moisture to get in and speeds up germination, but that’s by no means essential. And I just sow into an all-purpose potting mix. And of course, don’t forget you can sow squashes direct where they’re to grow. I’d sow maybe two seeds into each position and then thin out to leave the strongest seedling, just in case they both don’t germinate.

Some squash plants are pretty well-behaved. This lot definitely aren’t; these are proper sprawlers. Ideally, they need about 5ft or 1 and 1/2m between them. Now I’m going to plant them a bit closer than that, about a meter apart or 3 and 1/2ft, and the logic is that these ones towards the edge can sprawl out like big sort of spidery monsters, and I’m going to train a couple of them upwards so they won’t be sprawling out. So with that in mind, I’ve got these two rather pretty obelisks here. I’m just going to spike them over two of the plants, and that will add a lot of height and really add some drama to the whole proceedings. There we are.

The manure here isn’t quite 4in or 10cm like I thought it would be, so I might get some more. So what I’m doing instead is I’m digging down. I’ve cut a slit, opened out the cardboard, dug the soil here, and then for each squash plant, I’m going to give a couple of handfuls of this compost here and a scant handful of this blood, fish, and bone meal pellets. Something like comfrey pellets or chicken manure pellets would do as well. And then just fork that in. That’s better. It’s looking a bit more like it’s meant to. It’s quite clay soil here, so this will kind of help it just drain a bit better, and as I say, in another couple of weeks, we’ll probably be begging for rain and lamenting this kind of wet spell.

Right, that’s it all dug. Then out comes our Tonda Padana, this one, and then plant it in, comme ça, and firm it in, and then just return the cardboard flaps around the side as best as I can, and then the manure as well. There we go, that’s our first one. One down, nine to go. I started these off in the greenhouse, but it’s more than warm enough now to start them outside in most areas now. Before planting them, I was sure to harden them off over a period of about 10 days, bringing them out from the greenhouse during the day to sit outside in a sheltered spot, then bringing them back in on colder nights. But they’re fully hardened off now, and they’ll be in a home from home in this lovely sheltered spot.

So I’m going to get a bit more manure here just to kind of bulk it out a bit because it’s quite thin, but one of the things I will do once I’ve got that is just to create a kind of ring around each plant like this so that when I water, it holds it and it can drain through. Now as these sprawl, many of the stems will produce roots along their stems and root into this lovely rich manure, which will further help growth. So I don’t think I’ll need to add anything more in terms of nutrition here. That said, if plants do look like they could do with a boost, for example, if the fruits are still quite small and we’re well into summer, then I might well feed them with a high-potassium liquid tomato feed just to give them a boost.

One thing you could do to further reduce the risk of weeds is spread out a weed membrane and then cut holes into that and then plant through that. But seeing as this is quite a small patch and squash and pumpkin leaves just get so rambunctious and cover the soil anyway, I don’t really think that’s necessary, and it’s just more plastic. What I will do, however, is apply a little mulch of grass clippings. Now I’m going to add more manure later, as I said, but let me just show you what I mean by the grass clippings. I just spread them in a kind of thinnish layer like this, letting them rain down around the plants, and the idea is that this will just shade the soil, keeping the roots nice and cool. What else will it do? It’ll rot down and add further nutrition and, of course, make it another layer for those weeds to get through, and it kind of looks nice and pretty too once it’s done.

Okay, there we go. Now I’ll retop this up every kind of few weeks once the grass clippings disappear into the soil, but I reckon that looks pretty good.
Happy Gardening.

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