Giant Pumpkin Growing Guide

I am by no means an expert on this subject, but entering my sixth Giant growing season this year I have picked up a few tricks/tips that will help those new to the hobby

Patch prep:

Dig over your patch and dig in well rotted manure and rake flat, at the planting hole, dig out two wheelbarrows of soil and add the same back to the hole of well rotted manure, put the soil back on top and fork through to mix, you'll be left with a small mound into which you plant two plants, when they are starting to grow away, cut the weakest one down to the ground (do not pull it out as it disturbs the roots of the plant left in the ground). Pumpkins can be very heavy and thus difficult to move around so consider where it will be easiest on your patch to remove your harvested pumpkin from, then start your plants the opposite side. I made this mistake a couple of years ago.

Seed sowing/starting:

Pumpkins need heat and sunshine to grow well and a minimum soil temp of 10 degrees C, here in the UK we easily achieve that in summer, sometimes in late spring too. Timing is everything here, if you have plants that are ready to be planted but soil temp is still too cool then the plants will sulk and never really get away, this happened to me last year so it was an awfull season with no pumpkins for me.However it's not all doom and gloom and there are ways around everything, for example we can use simple cloches to cover plants straight after planting, that greenhouse effect will keep them nice and toasty unless we get late frosts.


Two plants in the ground at one side then covered in a makeshift cloche/hoop house 3ft high 4ft wide and 16ft long.

If you can provide the plants with the required soil temp, you can start your seeds around mid April, if your not sure then wait a few weeks into May sometime, you could also sow a couple of seeds, wait a fortnight and sow another couple to bolster your chances.

Looking at your seeds there is a pointy end and a blunt more rounded end and all over the seed there will be a slightly glossy lustre to it, you need to remove some of this lustre to allow mositure to penetrate it. Of course you could just pop the seed pointy end down into a pot of damp compost, but to improve your chances, do the following. Holding the seed by the pointy end (to protect it), use a piece of sandpaper to just remove that glossy lustre on the very thin edge of the seed, you can do this all around the blunt rounded end and down the edges too, but stay well away from the pointy end or you will damage the coteloden, and it is a very light sanding just to break that lustre. Now soak your seak in warm water for 12 hours or so, then place it in some damp cotton wool, in a bag and into a propogator, ideal temp is 28 degrees C. Germination should be around 7 days.

When your seeds have germinated, carfully dibble them into a 4 inch pot of compost, just leaving the very tip of the rounded end of the seed above soil level and put it somewhere warm and keep an eye on it, seed leaves should come up quite quickly now, then it's first true leaves, providing outside conditions are good it can be planted out. During this period you may need to repot it into something bigger, keep an eye on the bottom of the pot if roots start growing out from it, repot it to keep the plant moving

As I wrote above, you could just sow your seeds direct into a pot of moist compost, the above filing and soaking was developed for max germination rates as sometimes in the pumpkin community only one or two seeds are swapped/bought/sold.

Steve...

 

Planting out:

Ideally plant out two plants into your prepared mound 12 iches apart when soil temps are 10 degrees C or higher, I plant mine at a slight angle so that as it starts to vine away it is already pointing in the direction I want it to grow. If necessary, be prepared to protect the plants from late frosts, growth will be slightly slow to start.

Growing on:

When they do get growing, pumpkins are basically nutters and will try to take over the world so we need to control it, this is going to sound complicated but in reality it is quite simple to do.

Pumpkin plants grow out as a vine, meaning it will just keep growing out longer and longer, the first vine that grows from the plant is the main vine, every 12 to 24 inches along this vine the plant will grow a node. From this node the plant will continue growing towards its next node. From the node it will grow one leaf and eventually another shoot will grow from it that will become another vine. Vines that grow from the main vine are called "secondary vines". Secondaries, are "Mini me's" of the main vine so they too will grow out to a node, produce a leaf and eventually another vine will grow from them, these third vines are called teriaries and can be pruned out by us, the gardener. To undertsand it better, here are a few diagrams depicting this.







So the main vine grows to a node, puts a leaf up and continues growing to it's next node, the plant may well have grown to two or three more nodes and put those leaves up before you can see a secondary vine growing (or can identify it is a vine) from the very first node. When you have that first secondary vine approx 12 inches or more long, carefully move it so it is growing at right angles to the main vine and peg it down under an "X" of two short sticks/canes, that secondary vine will continue to grow and once it passed the pegging down by around 18 inches, remove the pegs and re-peg the now longer vine, maintaining it's 90 degree growth from the main vine.


The main vine is growing top to bottom in this photo, note how the secondaries are all growing outwards, left to right or vice versa, this would not happen unless you control and peg them down, it would be a complete mess, seriously diminishing your chances of good clean fruit. The arrow points to the end of the main vine.

Burying nodes:


Node root

As the main vine grows away to a node, produces the leaf and eventually its secondary vine and you have that pegged for the first time, now is the time to ensure that the underneath of the vine is in contact with the soil, to do this have a bucket of sieved soil or compost to hand and gently fill the gap between the underside of the node and the actual soil level, this will encourage roots to grow from that node that helps anchor your plant for the direction your growing it in and the roots also grab nutrients from that lovely soil you manured earlier in the season. DO NOT be tempted to use soil from the actual patch for this, pumpkin plants fill the patch with very fine white roots to just below the soil surface and upto a metre beyond the plant in all directions, any disturbance to the soil breaks these fragile rootlets.


Left to right is the main vine of a plant, notice that half of it has fresh soil under and slightly over it, watering and/or rain will wash it off the top of the vine but roots will grow out underneath.

 

Flowers:

From each node you will also eventually start to get flowers, normally the first flush of flowers you get will be all males, this is the plants way to make sure that when it does make a female flower, there is already a male available to polinate it. Male flowers tend to be taller at anywhere between 6-12 inches tall, female flowers are much shorter and have an easily indentifiable baby pumpkin directly behind the bloom. If you do not interfere with the polination process and just let the flowers bloom and for the bees to polinate it, this is called open polination, I do get involved though and try to cross plants, I'll post how I do that if asked to.


A two part illustration here, on the left is a side by side of a male and female flower, with petals cut away so you can see the stamens of the male and the females stigma, note the swelling underneath the female flower too. On the right is a very newly grown female flower, note the swelling again (a baby pumpkin), this flower is an inch long so you can easily identify male and female flowers.

Once the flowers have faded and you have two pumpkins growing, leave it a week then cut the smallest to concentrate growth into one fruit, From now on remove all flowers on the plant.

Caring for your swelling fruit:

Special care must be taken when handling the fruit a stray fingernail indentation when the fruit is young can cause a split as the fruit grows and swells, also prune out any foliage that may touch the growing fruit as this will also cause unsightly scarring on the fruit, gently train the fruit when young so that the fruits stem is growing away from the vine, dont go mad though..very gentle! I also make sure that the vine that the fruit is growing on has NOT rooted six foot before the fruit or after the fruit at all, this because as the fruit swells and grows it will start to lift the vine off the ground, so you need it to be slack enough to allow this.


The large yellow pumpkin here has suffered from scarring, dis id due to a combination of mishandling from me and abrasion from the foliage of the plant itself.


Lesson learned, no scarring on this 150lb fruit as I treated it carefully and pruned away foliage to keep the fruit "clean"

It's also preferable to not allow soil contact with the fruit, some place them on pallets or a few inches of sand, I use a sheet of polystyrene. In very hot and sunny conditions it may be necessary to shade the fruit too to stop the skin cracking.


Here I have placed the growing fruit onto the corner of some polystyrene.


Later on see how the fruit has "grown onto" the sheet, hence initially placing on the corner (above)


And space left around the fruit so it can grow unmolested.

Walk boards:

You have to be on the patch quite a bit, pegging down the main vine and secondaries, removing tertiaries and unwanted flowers and eventually cutting out tendrils, these are little green springs that will shoot out to help the plant anchor itself, cut them out to allow you to grow the plant as you want, the roots you encourage to grow will anchor it enough.

Anyway I use walk boards to spread my weight on the soil, so I do as little damage as possible to the fragile white plant rootlets, as the plant grows I move these boards outwards with it, but I leave a number of short length boards behind amongst the plant to act as stepping stones, this allows me to get in and around the plant later to prune out tertiaries and unwanted flowers.

 

Haarvesting your fruit:

Your fruit has a stem coming out and joining onto a vine, you should cut a few inches either side of this joining on the actual vine so you are left with what resembles a "T" shaped handle, NEVER use it as a handle though for any reason.

Hands off:

Relatives, friends and neighbours will marvel at the size of the pumpkin, they will want to rub it or even worse pat it, dont allow this at all. This bruises and wounds it.

Summing up:

I'm no expert but this is how I grow my plants, you could simply just put a seed in a pot of compost, let it germinate, grow and plant out, then harvest whatever fruit is there at the end of the season. I do it as described as it's a happy middle of the road method that gives me the best options to get a decent fruit at the end of the season, I could put a hell of a lot more in and set up misting lines and have soil and leaf tests done along with fedding the plants a long list of nutrients and trace elements.

So take what you want from the above or from others comments if they add to this topic later on (I hope they do!).

And lets hope at the end of the season, you can harvest your own "Smashing Pumpkins"





Steve...

 

Brilliant guide @Steve R

From a beginners point of view - I understood that very well & will definitely refer to it as & when needed! Thank you

 

quality post

A real good resource

 

This is really good advice. Does anyone else think this would make a good sticky? @Zigs what do you think?

 

Sticky Pumpkins

 

wow theyre huge! this is a really easy guide to follow so thankyou

 

What a fab post!

My wee girl brought a pumpkin plant home from school last week. The whole class have grown then from seed and each took one home. They've done so well....just hope mummy can look after "Peter Pumpkin" and get him to fruit!
Will he grow and fruit ok in a pot?I've repotted him into a decent sized pot....I just assumed it would grow like our courgette plants have done in past years which have grown perfectly in pots.

 

Bringing this forward as I just read this article ...
730kg giant pumpkin in Paderne could feed 3,000 people
According to Postal, a very large 730kg pumpkin has been cultivated in Paderne, Albufeira, and could be used to feed three thousand people.

By TPN, in News, Portugal, Algarve, Curiosity · 1 day ago ·


The farmers who made it hoped for their pumpkin, nicknamed “Claudinha,” to take part in the “My Village’s Biggest” competition, happening in Paredes. That won’t be possible, however, as the heat over the last few days has “cracked” it.

The vegetable’s future could now go to social charities that could give food to thousands of people in the form of pumpkin stew, in the case that it’s still in conditions for such.

Five months after the pumpkin was planted, it “couldn’t handle” the heat and made the hopes of José Rui Santos, the Paderne-based farmer, fall to the floor despite all the care he’d put in.

The farmer though, in the meantime, is happy that the weight achieved surpassed his pumpkin from last year, which weighed 699kg.

 

... and here's the guy with his previous Pumpkin ...
Portugal’s largest pumpkin “Isidora” is Algarve-grown - Portugal Resident

Paderne is about 20 minutes from me.