Grow Your Own Food with a Polytunnel: A Beginner’s Guide
Growing your own food is one of the most rewarding and empowering things you can do, especially in a world where food costs are rising and supply chains are becoming less predictable. Being able to produce fresh fruit, vegetables, and herbs at home or on a small block of land provides both security and satisfaction. For beginners, however, the unpredictable Australian climate can be daunting. That’s where a polytunnel comes in. This article will share everything you need to know to grow your own food successfully, without the stress of wondering ‘will it work’.
Why polytunnels are perfect for first-time growers
A polytunnel creates a sheltered microclimate, protecting your plants from wind, heavy rain, harsh UV, and sneaky overnight frosts. For new growers, this means you can start with confidence, knowing your crops have a better chance of thriving. Whether you’re building a self-sufficient backyard garden or planning to expand into small-scale market gardening, a garden tunnel is one of the best investments you can make.
The basics: What is a polytunnel and how does it work?
A polytunnel (sometimes also called a hoop house or high tunnel) is a structure designed to create an enclosed growing environment. Whilst some polytunnel structures are made with pine timber, every GROW Tunnel is built using hot-dipped galvanised steel, backed by a 10-year warranty, so you can count on a strong return on your investment for years to come.
Many cheap polytunnel options utilise a single sheet of polyethylene film as their cover. Whilst this will keep heavy rain off your crops, and trap heat in the tunnel, it won’t filter UV light and can result in overheating tunnels, and sunburnt crops. Whether big or small, GROW Tunnels are designed to commercial growing standards, utilising UV-stabilised Solarweave film, which filters light, diffuses heat, and creates a balanced growing environment. Unlike glasshouses, tunnels are affordable, flexible, and easy to install.
The principle is simple: the tunnel traps heat and moisture, creating a warmer, more stable environment than the outdoors. This helps plants germinate faster, grow more evenly, and produce longer into the season. Roll-up sides, insect netting, and shade cloth allow you to fine-tune ventilation, moisture, and light exposure. You can get to know how polytunnels work in more detail in this blog post.
Choosing the right tunnel size for your backyard
Polytunnels come in a range of sizes—from compact backyard models to large commercial spans. For beginners, size depends on your goals:
Small backyards: A 4m x 5m tunnel is a perfect size enough for herbs, salad greens, and a few rows of vegetables.
Medium gardens: A 6m x 9m tunnel provides room for crop rotation, space to prepare seedlings or grow microgreens, and a few extra raised garden beds.
Expanding growers: If you’re aiming to sell excess produce at markets, tunnels of 6m x 25m or larger allow for serious production.
The key is to start with a manageable space. A smaller tunnel that is fully planted and well-cared for will give better results than a large tunnel left half-empty.
Easy beginner crops to start with
The best way to learn how to grow food in a polytunnel is by starting with forgiving crops that thrive in protected environments. Here’s some of our tried-and-true favourites for tunnel growers, big or small:
Lettuce and salad mixes: Quick-growing and perfect for cut-and-come-again harvests.
Spinach, silverbeet and kale: Nutritious, hardy, and resilient to cooler nights.
Tomatoes: The ultimate tunnel crop, offering high yield, great flavour, and rewarding to grow.
Cucumbers: Easy to train vertically, saving floor space.
Herbs: Basil, parsley, coriander, oregano, sage and chives flourish in tunnels and are perfect for adding to culinary dishes, without needing to buy an entire packet from the store. Got a surplus? Cut and dry your own Italian mixed herbs.
Radishes and carrots: Quick turnover crops that help you learn soil management.
Starting with these will give you quick wins and valuable experience. Want more ideas of what to grow? Check out our ‘What to grow in a polytunnel’ blog article here.
Essential tools & equipment for tunnel growing
While you don’t need a shed full of equipment, a few essentials will make your growing journey much smoother:
Hand tools: A trowel, hoe, and pruning shears.
Watering system: Drip irrigation or soaker hoses are efficient and conserve water.
Thermometer and moisture meter: Helps monitor your tunnel microclimate.
Plant supports: Stakes, trellis, or GROW Towers for hydroponic crops.
Compost bins: To recycle garden waste into valuable soil nutrition.
Soil, compost and irrigation basics
Soil is the foundation of your garden. Start by adding compost or well-rotted manure to enrich organic matter. Raised beds inside tunnels can help improve drainage, especially in areas prone to waterlogging or with poor soil quality.
Irrigation is critical. Overhead watering increases the risk of fungal disease, so drip irrigation or soaker hoses are best. Pairing these with mulching helps retain soil moisture and reduce evaporation. Remember: consistent watering is better than occasional soaking.
Managing pests and diseases naturally
Even in tunnels, pests can sneak in. Prevention is key:
Aphids and cabbage white butterfly: Use insect netting and introduce beneficial insects like ladybirds.
Slugs, snails and caterpillars: Avoid overwatering and use organic traps.
Fungal diseases: Keep plants well-spaced and ventilated; water at the base, not overhead. Don’t overwater.
Rodents: Keep polytunnel doors shut, keep weeds down around polytunnel and use traps inside the tunnel if need be.
Polytunnels give you a head start by creating a physical barrier. Combined with organic methods, you can grow healthy crops without relying on chemicals. Read more about how polytunnels reduce the need for pesticides here.
Tips for maximising small spaces
Not every grower has acres to work with. The beauty of tunnels is how much you can produce in a compact space.
Vertical growing: Train tomatoes, cucumbers, and beans upward using trellises or use a hydroponic GROW Tower to grow up to 42 crops in 1m2.
Raised beds: Improve drainage and soil structure while organising crops efficiently.
Interplanting: Combine fast growers like radishes between slower crops like tomatoes.
Succession planting: Sow small amounts every couple of weeks for continuous harvests.
These methods allow even a modest tunnel to produce abundantly.
Mistakes to avoid as a beginner grower
New growers often make the same missteps, but they’re easy to avoid with some foresight:
Overcrowding plants: More is not always better—give crops space to breathe.
Ignoring ventilation: A tunnel without airflow can overheat quickly. Keep sides rolled-up when tunnel heat is high, and roll them down to keep plants cooler overnight if need be.
Inconsistent watering: Plants need steady conditions to thrive. Sensors can help beginner gardeners determine whether your plants are being over or underwatered.
Skipping soil prep: Healthy soil is the difference between thriving plants and stunted growth. The quality of what you put in, will determine what you get out.
Learning from these common mistakes will save you time, money, and frustration.
Start Small, Grow Big
Polytunnels empower anyone to grow their own food—whether for family meals or to supplement farm income. For beginners, they remove the biggest barriers: unpredictable weather, pest damage, and short growing windows. By starting with the right tunnel size, easy crops, and good soil practices, you’ll quickly gain the skills and confidence to expand.
The journey to a self-sufficient garden starts with just a few square metres under cover. With each season, you’ll discover new crops, new techniques, and new satisfaction in providing your own fresh, chemical-free food. Get an instant quote on a tunnel size that fits your space, growing needs and budget, or chat to one of our friendly team members by booking a call.
