The Best Way to Grow Courgettes in Grow Bags: Step-by-Step Guide

Courgettes (known as zucchini in some parts of the world) are one of the easiest and most productive vegetables to grow at home. Even if you’re short on garden space, growing courgettes in grow bags is a fantastic way to enjoy a huge harvest with minimal fuss.
In this guide, you’ll learn the best way to grow courgettes in grow bags — from choosing the right compost to watering tips, feeding schedules, and harvesting delicious fruits all summer long.

Why Grow Courgettes in Grow Bags?

Growing courgettes in grow bags offers several advantages:

Space-saving: Perfect for patios, balconies, and small gardens.
Better soil control: Grow bags offer excellent drainage and allow you to use rich, fertile compost.
Mobility: Easily move your grow bags to catch the best sunlight.
Reduced pests: Off-the-ground growing reduces slug and snail attacks.

If you’re dreaming of a bumper courgette harvest without needing a huge vegetable plot, grow bags are the answer!

Best Courgette Varieties for Grow Bags

Some courgette varieties are better suited for container growing than others. Look for compact, bush-type plants rather than sprawling vine types.

Top varieties ideal for grow bags:

‘Defender F1’ – Compact, disease-resistant, and highly productive.
‘Patio Star’ – Bred for containers and small spaces.
‘Eight Ball’ – Produces round, tennis ball-sized fruits.
‘Midnight’ – A compact plant with glossy dark green courgettes.
‘Gold Rush’ – Yellow courgettes, great for bright summer harvests!

Choosing the Best Grow Bags for Courgettes

Not all grow bags are created equal. For growing courgettes, you’ll need large, strong grow bags that can hold plenty of compost and allow room for roots to develop.

Ideal grow bag features:

Size: At least 40 litres (or roughly 10 gallons) per courgette plant.
Material: Thick, durable, breathable fabric that improves root health.
Drainage: Ensure the bag drains easily to avoid root rot.

Tip: Plant one courgette per grow bag for the best results.

Best Compost for Growing Courgettes in Grow Bags

Courgettes are hungry plants that love rich, moisture-retentive soil.

The perfect compost mix:

70% quality multi-purpose compost
20% well-rotted manure or garden compost
10% perlite or horticultural grit for extra drainage

Adding a slow-release vegetable fertilizer at planting time will give your courgettes a fantastic boost.

How to Plant Courgettes in Grow Bags Step-by-Step

Ready to get planting? Here’s how:

Fill your grow bag almost to the top with your compost mix.
Create a planting hole deep enough for the root ball.
Gently remove the courgette seedling from its pot and place it in the hole.
Firm the compost around the base and water in well.
Mulch around the base with straw or compost to retain moisture.

Important: Plant seedlings after the last frost date in your area — courgettes hate the cold!

Caring for Courgettes in Grow Bags

To get heavy crops of delicious courgettes, you need to stay on top of watering, feeding, and general care.

Watering

Water daily during hot weather — grow bags dry out faster than garden soil.
Always water at the base of the plant, not over the leaves, to prevent fungal diseases.

Feeding

After the first fruits start to form, feed weekly with a high-potash liquid fertilizer (like tomato feed).
Alternatively, use an organic feed such as seaweed extract.

Support

Bush varieties often don’t need support.
If your courgette gets top-heavy, use a small cane and soft ties to secure it.

Common Problems When Growing Courgettes in Grow Bags

Even with the best care, you may run into a few challenges:

Powdery Mildew

A white, powdery coating on leaves, common in dry, hot conditions.
Solution: Keep plants well-watered and remove badly affected leaves.

Blossom End Rot

Dark, sunken spots at the end of the courgette fruits.
Solution: Maintain even watering to prevent calcium deficiency.

Poor Fruit Set

Sometimes courgettes produce lots of flowers but few fruits.
Solution: Hand-pollinate flowers by transferring pollen between male and female blooms.

How to Harvest Courgettes from Grow Bags

Courgettes grow fast once they get going! Harvest when the fruits are young and tender for the best flavour.

Signs it’s time to harvest:

Courgettes are about 10–15 cm (4–6 inches) long.
Skin is glossy and firm.

Harvesting tips:

Use a sharp knife or scissors to cut courgettes away from the plant.
Pick every 2–3 days to encourage the plant to keep producing.

Top tip: Don’t let courgettes grow too big — large fruits reduce future production!

Conclusion: Big Harvests from Small Spaces

Growing courgettes in grow bags is one of the easiest ways to produce an impressive crop, even if you’re tight on space. With the right grow bags, rich compost, regular watering, and a little TLC, you’ll be harvesting basketfuls of tasty courgettes all summer long.
Give it a try — you’ll be amazed at how productive a simple grow bag can be!