Do Pumpkins Grow in Ireland?

Do Pumpkins Grow in Ireland?

Pumpkins can be a bit of a challenge to grow in Ireland, as they require a long growing season with good levels of sunshine - something that we can't really take for granted in this side of the world.

However, it is possible to grow pumpkins successfully if you provide the right conditions. Ultimately weather - specifically how the summer plays out - can play a big part here, and some years will be more favourable than others. 

Pumpkins on grass

Tips for Growing Pumpkins in Cooler Climates

Start them Indoors 
In Ireland we have a relatively short growing season at the best of times, so it's vital to give young pumpkin seedlings a head start by sowing seeds undercover, whether it's in a polytunnel, greenhouse, or on a sunny windowsill. The key benefit here is that the seedlings will be protected from any frosts, which pumpkins are very vulnerable to.

If you were to plant directly outside, you would have to wait until after the last frost date: which would be late May or early June. By germinating seeds undercover you can get started a few weeks earlier; all going well you will have a robust seedling and root ball ready for planting out. 

The ideal temperature range for germination is between 18-21°C, so a heated propagator is invaluable. The seeds should be planted in 7.5cm pots filled with multipurpose compost, with the ability to move on to a larger pot as the seedling grows. Sow the seed at a depth of 2.5cm, and place the seed sideways: this stops water from sitting on top.

small Vitopod propagator

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How Long Does It Take for Pumpkins to Grow?
In general pumpkin crops have a growing season of 3-4 months. However, if you opt for a faster-growing pumpkin variety, the crop will have a surer chance of reaching full maturity before the growing season peters out. 

It stands to reason that the earlier maturing varieties tend to also be smaller, but these have a charm of their own and are popular with children, whether it's the fist-sized 'Jack Be Little' or 'Baby Bear'. The medium-sized 'Racer F1' is also an early-maturing and productive bush variety.

Be aware that larger pumpkin varieties - such as those used for Halloween display or giant ones used for contests - will need plenty of time to mature, as well as plenty of space and nourishment.

Mini pumpkins

Provide Optimum Growing Conditions
Pumpkins are heavy feeders, so you should ensure that the soil has had a decent application of compost or well-rotted manure: preferably this should be done at least 6 weeks in advance of planting out. You can also add some chicken manure pellets as you transplant the seedlings.

Ensure they are planted in a sheltered, warm position (they don't like wind) and are getting plenty of sunlight. To maximise sunlight transmission, remove any large leaves so that they are not inadvertently shading the crop.

Some pumpkin varieties can be trained to grow vertically using sturdy trellises or plant supports, or their vines can be left to trail. There are also compact bush varieties, but 'compact' is relative here as they can still take up a good 3 feet of space.

Warm the soil in advance of planting out by using fleece, polythene or a mini tunnel for a couple of weeks beforehand. Space the seedlings or young plants well apart (1.5m for trailing varieties or 90cm for bush varieties).

Protecting Newly Planted Pumpkins
Unfortunately, slugs and snails are quite partial to young pumpkin plants. How to protect crops from slug damage is a vexing question that can trouble even the most experienced gardener. Beer traps are one of the more reliable slug deterrence methods. A more 'holistic' and long-term method is fostering the presence of natural slug predators, e.g. with the addition of a garden pond.

Summer weather can be unpredictable and capricious in Ireland. Be ready with some plant protection measures such as horticultural fleece or a mini tunnel frame which can easily be placed over rows of plants at short notice. 

Feeding and Watering
When the pumpkin plant starts fruiting, it's a good idea to supplement with a potassium-heavy liquid tomato feed every two weeks. As above, some chicken manure pellets are also recommended when planting out. 

Watering is crucial, especially during dry periods. Water well when they are first planted and again when they start to bear fruit. Measured irrigation around the roots (such as with drip irrigation and soaker hoses) is preferable to watering over the leaves, which runs the risk of leading to fungal disease or rot.

Adding a layer of mulch to the soil around the plant can also help retain moisture.

A ripening pumpkin

Harden Off Pumpkins Before Planting Out 
When transplanting the young pumpkin plants you should harden them off for 7-10 days. This means gradually getting them used to outdoor conditions: you can move the pots outside during the day and bring them back in undercover at night when temperatures drop. Alternatively use a cold frame and prop the lid open or closed as the case may be.

Keep Pumpkins Raised Off Soil
One of the big pitfalls to avoid when growing your own pumpkins is rot. Pumpkin skin may look tough but it can be sensitive to damage, whether it's during handling or from moisture. If skin is sufficiently damaged it can lead to rot and the skin won't be able to 'cure'.

It's important that your soil is free draining so that the plant is not left sitting in waterlogged soil.

When the crops are approaching maturity it is a good idea to raise them off the ground, using timber planks, bricks or cardboard. This will protect the outer skin from excessive damp, as well as garden critters like slugs.

Pinching Out Surplus Flowers
If you want to be harvesting an impressively-sized pumpkin, you should ensure that all the plant's energy is going into two or three fruits max. Pinch out any others and leave the ones that look furthest along. For giant pumpkin varieties, remove all but one fruit. 

Be Wary of Frosts in the Autumn
It's not just the young plant that is vulnerable to frost; a mature pumpkin plant can also come a cropper if it's subjected to unexpected cold temperatures. This can damage skin, leading to rot or making them unviable for storage.

Tasty pumpkin pie

It may be necessary to harvest a bit earlier than is ideal in the autumn for the sake of avoiding potential frosts. There's nothing quite as frustrating as having 3 months of healthy pumpkin growth before getting tripped up at the final hurdle. It's a difficult balancing act though, as if a pumpkin is harvested too early (see below) it will also be more susceptible to rot.

Either way, pumpkins will cease to grow once the temperatures drop too low.

Harvesting and Curing
Aim to harvest in early to mid-October when the foliage has died back and the fruit has had sufficient time to ripen. The ripening process sweetens the flesh but also thickens and hardens the skin.

To check if a pumpkin is ready for harvesting, give it a 'thump' and listen for a hollow sound. It should also have a deep, rich colour. Aim to harvest on a dry day; harvesting when wet can potentially lead to...you guessed it, rot.

Once they have been harvested or cut from the vine, pumpkins can benefit from a further period of sunshine. Since we will be into autumn at this point, this is best done in a greenhouse or polytunnel. The purpose of this is to 'cure' or harden the skin, which ensures that the pumpkins will store for a decent amount of time (up to 4 months).

Store at temperatures between 10-15°C and periodically check for any signs of deterioration and rot. Make sure the pumpkins are not touching up against each other as they are stored.

Carved pumpkins for Halloween

Conclusion
In short, growing pumpkins in Ireland is by no means an exercise in futility, but it can be a challenge - perhaps a welcome one! Halloween is a big deal these days (arguably a bigger deal than Christmas depending on the circles you run in), so having some homegrown pumpkins to harvest can add to the excitement.