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How To Grow Giant Pumpkins

Curious how to grow giant pumpkins at home? Well, you can and we’re going to show you how.

There’s a few reasons why someone would want to grow giant pumpkins. Maybe you’re trying to win a local pumpkin growing competition, or perhaps you simply want to impress your neighbors for Halloween. Whatever the case may be, knowing where to start can be tricky.

However, before you even think about growing giant pumpkins, you’ll want to familiarize yourself with any potential risk factors that could have a negative impact on your crop so you can take steps to avoid them. Common risk factors include:

  • Too much/little heat
  • Hail
  • Disease
  • Pests
  • Lack of proper nutrients

…and more. Once you’ve learned what steps you need to take to ensure your crop is protected, you can get the pumpkin growing process started. At Minneopa Orchards, we’ve grown plenty of pumpkins, including giant ones. 

With that said, we understand novices, who may not be as accustomed to the process, may be lost when it comes to what is required and where to begin. With this in mind, we’ve put together this giant pumpkin growing guide to help!

Seeds Are Key

How to Grow Giant Pumpkins: Planting Pumpkin Seeds

Anyway you slice it, the potential size of your pumpkins relies heavily on the seeds you use. Choosing your seeds shouldn’t be overlooked or something you do haphazardly. You should research what seeds will have the potential to grow pumpkins that are the size you’re aiming for.

After all, you can’t simply pick random seeds you find online and hope for the best. As former world record holder, Beni Meier proved in 2014 — with 3 record size pumpkins in a single season — the secret to growing massive pumpkins isn’t luck, but rather the right planning and hard work.

Beni showed us with the right technique along with mitigating risk factors (and a bit of help from Mother Nature) anyone who is willing to put in the work can grow giant pumpkins on their own. 

Sourcing Good Seeds 

Not all Dill’s Atlantic Giant seeds are created equal (especially if you are looking at department stores seeds) these may work for a large or even an extra-large pumpkin but usually, they do not have the genetic potential for a record size giant pumpkin. 

The good part is, if you ask a competitive grower, it’s likely he or she will share some of the seeds they use. Instead of just asking, though, we recommend sending them a nice letter or email with some kind words. 

Research Before You Buy

As we previously mentioned, doing your research is key to finding the right seeds. Otherwise you risk ending up with less-than-ideal results. 

Think of it this way: you might manage to get your hands on the best seeds from a competitive grower but these seeds may not do well in your soil or climate. This is why you should ask for advice from other growers, while taking the factors that are unique to you and your location into consideration.

These factors include the soil and nutrients you’re using, ph levels, and amount of light your crop will be receiving. 

Seed Names 

When looking for seeds, you’ll likely notice a series of numbers. These usually refer to the weight of the pumpkin and are followed by the name of the grower. 

For instance 2145McMullen (1756 Howell x 1625 Gantner) the following part refers to the weight and name of the mama seed and papa seed.

But a good seed can only take you so far, after all, it’s a balance of nature and nurture. Another key first step to growing giant pumpkins is ensuring you have the ideal soil ready for your seeds to be sown when the time is right. 

How to Identify “Good Soil” 

Giant Pumpkin on Display

When it comes to growing pumpkins, statistics show that the right soil determines about eighty percent of success.

You can start with a simple soil test. For this, you will need about 2 cups of samples from 8 different locations on the land you are planning to use for growing the giant pumpkins.  

You could contact Western Laboratories Inc for soil testing. Keep in mind, you should try to use the same testing lab every year for uniform information.

Post-Test Recommendations

Although these are paid recommendations, they are just as important as the test itself, John P. Taberna at western laboratories is very knowledgeable on giant pumpkins and can advise you on soil adjustments to help you amend your soil according to the giant pumpkins requirements.  

When to Amend Your Soil

The right time to amend your soil is during the fall, however you can also make small adjustments in the spring. Use the recommendations after the soil test to plan your soil amendments. 

Soil Amendments 

Good soil is balanced with calcium, magnesium, and potassium for optimal growth. 

Often you see “PPM” with reference to soil nutrients this refers to Parts Per Million. 

It is advisable to take a look at the parts per million guidelines for soil numbers after your soil test using the test as a guide. Atlantic giants are accommodative of a range of soils however for a truly giant pumpkin you must try to be as specific with nutrient needs as possible.

Organic Matter 

Good soil contains approximately four to nine percent of organic matter. Some good sources of organic matter are compost, grass clippings, Alfa Alfa pellets, and peat moss. 

Organic matter retains soil, adds nutrients, creates air pockets, and buffers ph swings (the ideal ph level is between six point seven to seven or twenty to forty PPM). Organic matter also improves soil texture. However, it’s important to note that with fifteen percent or more organic matter you are at risk for pathogens. 

Nitrogen

In the first half of the season, plants need more nitrogen to grow leaves and stems but be wary of heavy rains as it causes nitrates to flush out.

Be sure to watch the plants’ leaf color for hints of this occurring. Yellow indicates a nitrogen deficiency. Some sources of nitrogen are blood meal, urea, and fish fertilizer. 

Phosphorous 

Rooting and flowering takes up twenty-five to sixty percent of the plant’s energy. Monoammonium phosphate has shown to provide twenty percent more root growth 

if used in the first week of plant growth. 

Phosphorous is an essential energy element for rooting and flowering. However, it is hard to get out of the soil so don’t overdo it to keep the soil in a happy medium. 

Potassium 

Typically giant pumpkins will need around three seventy-five PPM. If that seems like a lot, remember that pumpkins consume more potassium. Some great potassium sources include leaves, compost, kelp meal, and greensand.

Give it an extra boost during heavy fruiting and flowering because the plant can deplete potash (various manufactured and mined salts that contain potassium in water-soluble form) early on while fruiting, sometimes as soon as just three to four days. 

Be mindful, however, as high levels of potash in the soil is antagonistic to the update of calcium and magnesium. 

Calcium 

Calcium is critical for pumpkin growth. Around 2,200 PPM is needed to build cell walls and activate enzymes that turn on “growth hormones”  Some great sources of calcium are gypsum, and calcium nitrate.

Micronutrients

With a balance of boron, copper, manganese, iron, and zinc you can amend the soil using caution depending upon the soil test recommendations. 

Cover Crop

This is important to grow giant pumpkins just as it is in all farming. It builds organic matter, adds to nutrients of soil, builds soil biology, keeps soil from getting compacted and even suppresses weeds. 

As a cover crop, you can plant a crop like winter rye in early fall. Be sure to till the area two weeks before planting. After making sure you have the right soil you can focus on starting the seeds. 

Seed Prep 

2 Giant Pumpkins

For those in the United States, tax day is a good target for planting your seeds (depending on your environment). For an extra boost, lightly sand all sides except the pointy end of the seed to help the plant get going. 

You can add a drop of liquid seaweed and a touch of humic acid and soak the seeds in water for 24 hours before planting.

Seed Starting

Take a moist paper towel and put the seed in it then put it in a zip lock bag; placing the bag in an area that is about eighty to ninety degrees Fahrenheit for twenty-four to forty-eight hours. 

Or you could plant the seeds into seed starting mix, adding mykos azos and worm castings. Make sure the temperature is eighty to ninety degrees Fahrenheit, also make sure the soil temperature is warm enough and the seeds get plenty of natural light or use glow bulbs. 

A good idea is to use a slightly larger pot to start seeds as the roots grow fast and you want to avoid the roots getting bound up. 

Transplanting  

When you transplant your pumpkins into the soil you must be gentle with the roots. You can add myco, azos, actinovate, and root shield to the planting hole. 

Water the plant well with warm water or prepare your aerated compost tea. Position the plant so that the first true leaves face the opposite direction of where you want the vine to grow. The plants may wilt after you transplant them, don’t worry, this is normal. You may need to shade the plants for the first few days after transplant. 

Make sure to do the usual vine maintenance by pruning, removing tertiary vines and tendrils if needed also remove taproots from vines near the pumpkin. Guide your main vine gently over the days to reduce vine stress in case of a c vine, moving it during the day. 

Controlled Pollination

Identify the female flower (the ones with small fruit ovary attached) and shade it to protect it from rain and irrigation. 

Add pollen from the male flower to the female flower by hand then cover the female flower again (this should be done in the early morning). Once the fruit begins to grow you can place it on sand or fabric. 

Fertilization

Since the soil has been tested, amended, and so on, you’re off to a great start, feed the plant small amounts of nutrients daily. Make sure to adjust according to plant needs and environment. 

Ideally, small amounts fed continually makes for optimal growth. Initially, 4-4-4-4 Nitrogen Phosphorus and Potassium works well. You can also use a 7-4-5 fertilizer until three weeks after pollination, and a 3-12-12 after pollination. 

Not all fertilizers have the same quality quantity or even integrity so it is essential to research the ideal brand and nutrient balance for your needs. Reading labels is a good place to start, noting the package weight and identifying the pounds of fertilizer and sugars will save you the money you would otherwise waste on fertilizers that are 99% water.  

Fungicide & Insecticide 

Disease can ruin your crop season quickly, in some areas fungicides are needed more than others. However, you should be mindful of the natural after-effects of insecticidal and fungicidal use. 

Try to use natural fungicides like sesame seed oil, and neem oil. An easy cure for powdery mildew is equal parts milk and water to be sprayed at noon in bright sunlight. The sunlight reacts with the calcium in milk killing the mildew. Be kind to the bees and use insecticides only if you must (preferably after sunset). 

Have Fun Growing Your Giant Pumpkins!

While the process can be quite daunting and laborious, it’s important not to forget to enjoy growing your giant pumpkins.  

Remember, the keys to growing giant pumpkins effective are testing, patience, research, mixed with a bit of trial and error. With the tips listed above, however, you’re sure to find success in growing giant pumpkins, even if it’s your first time. 

Excited for more pumpkin content? Keep learning all about pumpkin plants to become an expert on pumpkin planting, growing, harvesting, cooking, and more!