Growing Giant Vegetables
If you’ve ever admired oversized pumpkins or towering zucchinis at the Home Harvest Awards during the CERES Harvest Festival, you may have wondered: How do they grow so big? Growing giant vegetables is both an art and a science, requiring a combination of skill, dedication, and a bit of luck. Below are some tips to help you succeed – but the best strategy is simply to have a go.
Go on, you’ve got beginner’s luck on your side!
1. Start with the Right Seeds
Giant vegetables start with seeds that have been selectively bred for size. Over generations, seeds are collected from the largest fruits. Here are some “large and in charge” varieties you might find at the CERES Nursery:
- Musquée de Provence Pumpkin: Delicious as well as large, with fruits weighing 5–10kg.
- Mortgage Lifter Tomato: This heirloom tomato produces fruits of up to 1.5kg!
- Long Purple Eggplant: Produces fruits up to 25cm in length.
- Scarlet Emperor Runner Bean: Known for pods that can grow up to 30cm.
- Cocozelle Zucchini: These grow fast and can reach up to a metre long if left on the plant.
- Cucuzze Gourd: Known by different names all over the world, this squash grows pale, straight and very long, to a metre or more. While we don’t sell the seeds, we occasionally have some to give away, thanks to award-winning gardener and CERES Nursery regular Paul. Ask for some on your next visit to the nursery!
2. Prepare Your Soil
As with all gardening, healthy, nutrient-rich soil is key. Giant vegetables are particularly hungry, so they’ll need a fertile spot to thrive. An old, well-rotted compost heap is ideal.
3. Provide Plenty of Space
Giant vegetables need room to grow, both above and below ground. Overcrowding can stunt their development. Plan your garden layout carefully, giving each plant ample space to sprawl or expand. If space above ground is limited, growing vertically on a trellis can work wonders.
4. Water Wisely
Consistent, deep watering is essential for giant vegetables. However, overwatering can cause splitting, rot, or disease. This is where the art of gardening comes in – over time, you’ll get a sense of what works best. Avoid watering foliage to help keep fungal issues at bay. Mulch can help retain soil moisture and regulate temperature, ensuring your plants stay happy and reach their full potential.
5. Feed Frequently
Oversized vegetables are heavy feeders. Start with fertilisers rich in nitrogen early in the season to encourage leafy growth, then switch to phosphorus- and potassium-heavy blends as the plants begin to fruit.
6. Prune Strategically
Focus the plant’s energy on fewer fruits or flowers by pruning. For example, remove all but one or two fruits from a pumpkin vine to allow those selected to grow larger.
7. Protect from Pests and Diseases
Giant vegetables can attract pests and diseases that could jeopardise your efforts. Spend time with your plants daily to check for issues such as aphids, slugs, or caterpillars. Certain plants attract beneficial insects that naturally control pests. We sell a Beneficial Critter Seed Mix, designed to provide food and shelter for pollinators and predators alike.
8. Provide Support
Many giant vegetables, such as tomatoes and melons, need physical support. Use sturdy stakes, trellises, or slings to keep fruits off the ground and prevent damage from their weight.
9. Start Early
Plant as early as possible to maximise growth time. If you have a cold frame or greenhouse, you can give your seedlings a head start indoors before transferring them outside.
10. keep a garden diary
Every growing season is a learning experience. A garden diary can help you track your progress, remember what worked, and improve for next year. Record details like seed selection, soil preparation, watering schedules, and fertilisation methods. Experiment with new techniques to see what suits your garden best.
Whether you’re aiming for a personal best or hoping to win an award, the satisfaction of nurturing a colossal creation is worth the effort. Even if your vegetables don’t turn out as planned, you might still take home the prize in our “Most unusual” category!
CERES Harvest Festival
The CERES Harvest Festival happens each March, celebrating the seasonal abundance of late summer at CERES Park in Brunswick East. The Home Harvest Awards are a chance for local gardeners and cooks to showcase their skills, connect with fellow plant enthusiasts, and win prizes on the day.
Gardening award categories
- Biggest fruit/vegetable
- Longest vegetable
- Most unusual fruit or vegetable
Bottling award categories
- Best seasonal jam
- Best seasonal chutney or relish
Baking award categories
- Best cake
- Best slice/biscuit
How to Enter
Sign up for our newsletter below or follow us on social media to be the first to know when entries open in the lead up to the festival.
by Andrea Nelson
CERES Nursery enquiry
- Growing giant vegetables
- Pollination explanation
- Bare-root fruit trees explained
- Garlic planting, CERES style
- Growing tomatoes 1 – choosing the right one for you
- Growing tomatoes 2 – seed-sowing and transplanting
- Growing tomatoes 3 – watering and fertilising
- Growing tomatoes 4 – staking and pruning
- Growing avocado trees
- Seed potatoes – what are they?
- Bare-root strawberry runners
- Growing asparagus
- Bee-friendly gardens
- How to rehome a rooster
- CERES Nursery – Educating for food security
- Recipe: Nigethan’s Garlic Dahl
- Meet the Terra Wonder Playspace designer
- What is the significance of Winter Solstice?
- 5 myths we wish were true about CERES
- Smart urban forests at Brunswick East
- Solar projects at Brunswick East
- The Sacred Kingfisher
- From Classroom to Creek
- What happens on a corporate volunteer day?
- The sad loss of our DIG office
Keen to keep learning?
CERES has over 70 Workshops & Courses covering gardening, cooking, traditional crafts, nature connection and more. Learn small space growing, fruit tree pruning, urban farming and more.