Atlantic Giant Pumpkins 

Atlantic Giant Pumpkins are a popular variety of pumpkins known for their massive size and impressive growth potential. These behemoths can weigh up to several hundred pounds locally (1000’s in better-growing areas) and are a favourite among specialized pumpkin gardeners and enthusiasts alike. In this comprehensive guide, we will delve into the details of planting, growing, harvesting, and storing Atlantic Giant Pumpkins, ensuring that you can successfully cultivate these giants in your garden.

Days to Grow100-120 days
Square Foot Garden Spacing8-10 feet apart
Gardening EffortModerate
When to Plant3-5 weeks before last frost
Yield1 large pumpkin per plant
Frost ToleranceTender (not frost-tolerant)

Gardening Shortcut Links

Square Foot Gardening Section

Planting Atlantic Giant Pumpkins

Atlantic Giant Pumpkins were developed through selective harvesting for decades by Howard Dill in Windsor, Nova Scotia, my hometown. Since then, the seeds have been grown worldwide and commonly produce 400-500 pound pumpkins. Record-sized pumpkins in access of 1000 pounds are common.

To ensure the success of your Atlantic Giant Pumpkins, start by selecting high-quality seeds from a reputable supplier. Opt for seeds with a proven track record of producing giant, healthy pumpkins. Once you have your seeds, choose a planting site with well-draining soil, rich in organic matter, and ample sunlight.

Starting Seeds Indoors

Begin by starting your Atlantic Giant Pumpkin seeds indoors 3-5 weeks before the last expected frost date. Plant the seeds in larger pots filled with a well-draining seed-starting mix. Keep the seeds consistently moist and maintain a temperature of around 70°F (21°C) to encourage germination.

Preparing the Soil

Before transplanting the seedlings outdoors, prepare the soil by incorporating plenty of organic matter, such as compost or well-rotted manure. This will provide essential nutrients for your pumpkins and help improve soil structure. Also, consider performing a soil test to determine the pH level and nutrient availability. Ideally, the soil should have a pH of 6.0 to 6.5.

Transplanting the Seedlings

After the last frost has passed and the soil temperature reaches at least 60°F (15°C), transplant the seedlings outdoors. Space the seedlings 8 to 10 feet apart in mounds or hills, ensuring that each plant has plenty of room to grow. Be careful not to disturb the roots when transplanting, as this can reduce your pumpkins’ growth.

Growing Atlantic Giant Pumpkins

Watering and Fertilizing

To support the growth of your Atlantic Giant Pumpkins, provide consistent moisture throughout the growing season. Water deeply and regularly, aiming for at least 1 inch of water per week. Avoid wetting the leaves, as this can encourage the growth of fungal diseases.

Fertilize your pumpkins with a balanced, slow-release fertilizer at planting time, then switch to a high-potassium fertilizer as the plants produce fruit. Regular applications of compost or well-rotted manure can also provide necessary nutrients and improve soil structure.

Pruning and Training

As your pumpkins grow, prune the vines to encourage larger fruit development. Remove secondary vines, leaving only the main vine and a few tertiary vines. Train the main vine along the ground, gently curving it to prevent stress at the vine’s base.

One “trick” is to bury individual vine nodes (where the vine splits into multiple vines). When buried, these nodes will form roots and feed your giant pumpkin even more. So instead of one root feeding the pumpkin, you can have 2, 3, or 10. 

To focus the plant’s energy on a single fruit, select the most promising pumpkin and remove all others. Then, place a piece of plywood or a plastic mat under the chosen fruit to keep it clean and prevent rotting.

Pest and Disease Management

Monitor your Atlantic Giant Pumpkins for signs of pests and diseases. Common pests include squash bugs, cucumber beetles, and aphids, while powdery mildew and bacterial wilt are frequent diseases. Employ integrated pest management techniques, such as companion planting, crop rotation, and using organic pesticides to protect your pumpkins.

Harvesting Atlantic Giant Pumpkins


The ideal time to harvest your Atlantic Giant Pumpkins is when the fruit’s skin has turned a deep, uniform orange and the stem has become brown and dry. Additionally, the pumpkin should emit a hollow sound when tapped. Depending on the growing conditions, this usually occurs around 100 to 120 days after planting.

To harvest, use a sharp knife or pruning shears to cut the stem, leaving a few inches attached to the pumpkin. Avoid lifting the pumpkin by the stem, as it may break and expose the fruit to rot.


After harvesting, cure your pumpkins to prolong their storage life. Place them in a well-ventilated area, protected from direct sunlight, with temperatures between 80°F (27°C) and 85°F (29°C) for 10 to 14 days. This process helps to harden the rind and heal any minor cuts or abrasions.


Growing Atlantic Giant Pumpkins can be a rewarding and exciting endeavor for gardeners of all skill levels. By following the guidelines provided in this article, you will be well-equipped to plant, grow, harvest, and store these magnificent pumpkins. With careful planning and attention to detail, you can successfully cultivate and enjoy the fruits of your labor, possibly even breaking a few records along the way.



Seeds and planting
Links and Resources

Recommended Products
(These are some of what I use)

These nursery bags
These Grow bags

Pages Seeds Page
Get a Head Start on Spring: The Benefits of Starting Your Seeds Indoors
Saving Vegetable Seeds: A Comprehensive Guide to Gardening Success Planting Guide
Pollock Tomatoes (North hardy Tomato variety)
Tomatoes (Useful information on starting tomatoes from seed)

DIY Garden Irrigation System: A Detailed Guide for Northwest Ontario

Blog Posts

When to start planting seeds
Germination testing your seeds
Looking for sources for seeds?
Heirloom seeds
Chitting your way to more potatoes
So it's before the first frost; what can I plant?


Individual seed and plant information is available in the  "Gardening Shortcut Links" above under "North Hardy Plants to grow". I have successfully grown all of these, and most I grow year to year.






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