What is a polytunnel and what can you grow in one?
Rain’s dripping off your coat as you reach for a lettuce under the polytunnel cover. The leaves are dry, ready for picking. So is the soil beneath them: rain hasn’t reached this bed, and watering is still your job.
Tomatoes get a sheltered summer spot, and salads have a longer season in a garden polytunnel. A commercial polytunnel does the same over more ground. There’s still work: an April morning starts cool, then sunshine heats the space and somebody needs to open the doors.
How does a polytunnel work?
Stand inside on a windy day. Above you, polythene stretches across curved hoops, sheltering the crops from rain and taking the force out of the wind. Sunlight warms the soil and other surfaces beneath it. Getting too hot? The doors and ventilation openings give warm air a way out.
Heating? None comes with that arrangement. After sunset, temperatures drop again. Frost still reaches tender plants in a commercial polytunnel, so the size of the structure doesn’t spare you the job of protecting them.
You have had rain all week, yet your finger comes out of the bed dry. Most crops grow in these beds; pots work too. Neither gets watered by the weather as they are all protected by the tunnel cover, that’s your job.
What can you grow in a polytunnel in summer?
A ripe tomato hangs behind a supported stem, beyond your reach. Squeeze through and you risk snapping it. Space left at planting makes picking easier later; regular watering matters too. Cucumbers, peppers and aubergines also suit that sheltered warmth.
Two nursery pots of courgettes take up little space. Give those plants a bed and their spreading leaves soon crowd neighbouring crops, with other large, hungry plants competing for what’s left.
In a commercial polytunnel, the choice depends partly on what customers will buy. At home, it depends on what you’ll eat. Twelve tomato plants aren’t much use if you’re away through August and nobody’s picking them.
Basil fits beside summer crops where it has enough light, and climbing French beans use the height if their supports hold firm. Melons leave less room for mistakes with warmth and watering. For a first crop, that means more watching.
Can you grow vegetables through a UK winter?
Yes. Expect leaves to grow slowly.
Want spinach, winter lettuce, lamb’s lettuce or claytonia to pick in winter? Sow early enough for roots and leaves to establish before the short days put growth on hold.
Miss that start in a commercial polytunnel and the cover won’t make up the time. A bare November bed on an allotment has the same problem: Christmas is too close for it to become a full salad bed.
Broad beans and young plants destined for outdoor beds need somewhere to start. They fit here, provided you’re willing to give them space your winter leaves could occupy.
Winter tomatoes are another matter in an unheated tunnel. A plant still standing in January isn’t the same as ripe fruit on your plate.
Is a polytunnel greenhouse combination worth considering?
Where would your seed trays go in a polytunnel greenhouse setup? Rigid glazing, benches and room for small pots give a greenhouse its use; the tunnel puts a flexible sheet over growing beds. Having both means two spaces to water, ventilate and repair.
With a commercial polytunnel, production depends on how much ground you can grow in and how easily you can reach it. At home, there’s also the kitchen window: what fills the view, and is there still room to hang the washing?
Leaving things outside is a fair option. Potatoes, kale and many other vegetables don’t need a roof, and an outdoor bed costs less to establish.
What does a polytunnel cost, and can you put it up yourself?
What does £100 to £300 get you? A small, lightweight garden kit. Several hundred pounds through to thousands buys larger walk-in space with a stronger frame. A commercial polytunnel needs a quote for its width, length, doors and installation.
Compare what’s supplied. A low headline price tells you little if anchoring materials and delivery cost extra.
You and a helper have a weekend free for assembly. For a modest garden kit, that’s realistic if you’re comfortable following measurements and instructions. But levelling uneven ground takes extra time, and a large cover becomes difficult to handle when the wind catches it.
Paying installers saves that work, though access and ground conditions affect the charge. Ask for assembly to be priced separately. Nobody can give you a useful installation figure without knowing the structure and site.
What needs attention once it’s growing?
Cucumber leaves hanging limp on a hot afternoon? Check heat and watering; opening doors before temperatures climb helps prevent overheating. A watering fault in a commercial polytunnel leaves far more plants struggling.
Scratch beneath that pale soil crust before adding water. It could still be damp below. Aphids along a shoot or diseased leaves need attention while you’re looking.
Measure your ground today and
put two crops beside those measurements on paper. Will the anchors fit that
site? Compare the commercial polytunnel or garden model’s anchoring
instructions with your measurements. Get in touch if you’d like to discuss the
space and crops you have in mind.
Read More :
How to choose and replace a polytunnel cover
Comments
Post a Comment