This year I decided that I wanted to grow a few pumpkins. I like Pie. So I went and started some seedlings, planted them, and a few weeks later they were thriving and happy pumpkin vines. However I ran into a slight problem. Connecticut Field Pumpkins grow like mad. They were threatening to take over my garden and the back yard.
I needed space for my tomatoes, aliums, and other cucurbits, so I scoured the internet. Somewhere, I found a picture a guy had of a forest somewhere--with pumpkins growing in a tree. The vine had apparently climbed the tree, and set fruit high up in a tree. There's also this news article about the Greenfield, Iowa couple who found a pumpkin growing in their pear tree.
So I thought to myself, if they can grow in trees, why not up and onto the roof of our garden shed?
Step 1: Have the Right Pumpkins, Soil, and Time
Most seed packets dictate 100 days from germination to harvest. So get moving on the planting part or it might be too late. Seeds ought to be planted relatively close to the surface you're going to trellis them up. Once the vine gets thick and mature
it will be much more difficult to train without risking breaking it.
Additionally your choice of pumpkin should be vining, and of a small or medium variety. While growing a record breaking pumpkin
on your roof may sound like a neat idea, it could cause water to pool on your roof, causing damage to shingles. The other reason you need to keep the pumpkin size down is that you have to get it down some day.
A good rule of thumb is this: Grow pumpkins no larger than the heaviest thing you can carry up and down a ladder, without assistance. A record-breaking pumpkin could break you.
I selected Connecticut Field Pumpkin, which is the classic "Jack-O-Lantern" pumpkin, and of a medium weight (25-50 lbs). Being medium sized pumpkins with long, vigorous vines, they're well suited to this sort of trellis.
Additionally, you may wish to use landscaping fabric and mulch around the base of your pumpkins--all the way up to the side of your structure. This prevents grass and weeds from growing in between your plants and the building, and controls insects
Step 2: Effect Necessary Repairs
I thought I'd include this bit of common-sense advice here. You shouldn't build a trellis like this up against the side of a wall if you suspect that you might have to paint or repair that wall during the growing season. Pumpkin vines get brittle, and break easily. I can't imagine anything worse than losing a bunch of pumpkins because you broke the vine.
Pictured is a female flower. You don't want to lose these girls, because they get big, orange, and delicious in pie. The leaf next to it was broken off accidentally. Breaking leaves and stems is something that should be avoided at all costs. Hence most of your construction should take place while the vines are young.
Step 3: Tools and Materials
For this project you will need to beg, borrow, steal, buy, recycle, build, or up-cycle the following
- Hammer, Saw, general carpentry tools
- A staple gun, such as that used for insulation
- A ladder of sufficient height or a ladder of nearly-sufficient height, and an assistant
You will need to beg, borrow, steal, or recycle the following
-Wire fencing material
-2 1/2" galvanized nails
-Jute Twine or similar
Step 4: Constructing the Trellis
The trellis is constructed by simply attaching the wire fencing material, mine is a 2" coated square mesh, to a handy wall. The wire serves as a place to tie the vines, and as a place for the vines to tie themselves via tendrils. Ideally your wire ought to be the same width as the distance between the stud-centres of your building. The 1x2 pieces of lumber serve to hold the wire a ways out from the building so that it will not trap water against the siding.
I used bent over nails to fasten the wire to the trim, and 1x2s as my staple gun is only fit for insulation installation and not the sort of thing that can nail fencing material to posts. A helper is handy at this point.
Step 5: Training Your Vines -- Part I: Up the Trellis
This is the part where I wish I had done this a week or two ago. While training one of the vines, I snapped off the growing tip. It's not the end of the world as far as this vine is concerned as the lack of Auxins in the dominant tip will cause the vine to sprout a new one. I used insulated copper wire to loosely tie the vines to the wire mesh. They'll eventually hold on by themselves but for now, this works as a good suggestion.
Try not to break stems. They tend to be brittle in older plants. If all the leaves aren't facing towards the sun, don't worry. Phototropism will fix that in a few days. Maturing fruit will need additional support if it develops on the trellis. Fortunately since I have an existing structure behind my trellis--I can easily attach slings to support fruit. If it develops on the roof, you win!
Step 6: Training Your Vines -- Part II: Beware the Eaves of May
Eaves and overhangs present a problem. Phototropism dictates that the vine will always grow away from the eave and towards the closest major light source. That light source being the sun, my vines all tried to grow directly into space.
Pumpkin vines cannot grow to space, unless you own a rocket company so I had to correct this matter. Their stems are strong, yet brittle, and will collapse if left unsupported by things like the ground. Therefore one must gently bend the spaceward-stems, and anchor them to the roof of the victim building.
The part of the vine unsupported, and growing upwards, needs to be around a foot long, so that you can gently bend it towards the roof. Any shorter and you risk breaking the vine. Any longer, and the vine might break itself for you. Pumpkin vines grow very, very fast, and so you have to be quick here--even if it means going up on a roof at night with twine & stapler in you hands, and scissors clenched in your teeth like a really weird pirate.
Step 7: Training Your Vines Part III: Anchoring, and Maintenance Pruning
If you live in Oklahoma, or any similar place where winds tend to come sweeping down the plains, you'll want to work on properly anchoring your vines to the roof. Although pumpkin tendrils will do some of the work here, you need to give your vines a bit more anchoring. This is where your precious fruit will form, ideally speaking.
I used the same staple-and-loop system that is shown in the previous step. A short length of twine is securely stapled to the shingles, and then loosely tied around the vines it needs to anchor in place. So far my vines have survived 40 MPH winds without any trouble whatsoever. You'll probably need to get up on the roof again.
For general maintenance pruning, try and keep your vines on the trellis and roof. Clip off any growth tips that are going where you don't want them to go. This should be done when the errant tips are young, to save the plant's energy. Thanks to their double-vascular system, pumpkin vines are extremely vigorous, and we want pumpkins on the roof--not on the ground!
When you add more anchors, try and guide your vines towards the crown of the roof, keeping them away from the edges.
Step 8: Go on a Panty Raid, and Help Flowers Make Sweet Love
Growing pumpkins on the rooftop gives you an additional measure of control. Rather than waiting for the bees of the world to get their collective acts together, grab some scissors and a ladder.
On my vines, most of the male flowers developed at a lower level than the female flowers. Thus I very carefully clipped the pollen laden anthers out of the male flowers (I have heard you can eat the blossoms, if you fry them), and gently rubbed them onto the anthers of the female flowers.
Male pumpkin anthers look a bit like those miniature corn things you get in stir fry bags at the supermarket. Don't be afraid to clip off female fruits that would have developed in an inconvenient location.
Does hand pollination work? Look at the picture. The pumpkin hanging in the generously "donated" hosiery is only about two weeks old. That is your supermarket-sized apple, for comparison's sake. I suspect this pumpkin will need additional support soon.
Step 9: Admire Your Use of Previously Unusable Space, Brag to Friends and Neighbors
This step is largely self explanatory. However I feel that this method of growing pumpkins holds great promise for the gardener with an extremely limited amount of space in their backyard. Pictured are my six vines. It doesn't have to be a garden shed. It could be anything. You could even grow pumpkins up a tree as that one couple in Iowa found out. The vines have the vigor to grow wherever you will guide them.
So what was it that the Mythbusters say? Ah yes. Myth Confirmed!
Step 10: Harvest Pumpkins!
This step is a bit self explanatory. You need to cut ripe pumpkins from the vine with a sharp knife, leaving about three inches of stem on the fruit. Let your pumpkins cure in the sun till the skin is hard. The pumpkin in this image was harvested around June 3rd.