Growing Guide

Welcome to our Premier Polytunnels Growing Guide, where you will find great hints and tips on how to get the best from your Polytunnel each month. Inspirational tips and handy tricks that we have picked up over the years.

  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
Jan

January's Top Tips

January's Top Tips

January often feels like a long month for many people and although January is a calmer month in the polytunnel, time really does fly and the busy growing months will soon be upon us.

Start as you mean to go on and draw up a cropping PLAN for inside your polytunnel this year. Consider what worked well for you and your plants last year and plan any changes you want to make, eg, to the layout, in your tunnel.

If not already done, SORT out any plant labels and ORDER seeds ready for the busy late-winter and early-spring months. Don’t forget that a polytunnel stretches the growing season at both ends of the year – You do not want to wait too long for your seeds to arrive and miss your first chance of sowing.

Keep on top of TIDYING and REPAIRING the polytunnel cover. Algon is the ideal way to clean the polytunnel cover, and repair tape acts as a plaster for the polythene when strong winds cause debris to fly past.

A British winter can be very wild, so be PREPARED for bad weather – Secure your polytunnel against strong winds and storms by ensuring that door catches are fixed tight and that doors and side vents are secure. Doors which rattle in gales can be reinforced using timber braces or a heavy weight against the door. We recommend that heavy snowfall is brushed off the tunnel as soon as possible. The weight of a big snowfall can put strain on the frame and may cause the polythene cover to stretch and sag if left to lie on the roof. REMOVE excess snow by tapping on the sides of the cover and the roof if you can reach. Use a gas or electric heater inside the tunnel to turn up the temperature and encourage the snow to slide off. Use a soft brush to know snow from the harder to reach areas.

If you are using your polytunnel for propagating, ensure pots and trays are not left on the floor – MOVE them onto staging to give the plants better conditions and prevent slug damage. Trestle Staging is a simple, practical and portable staging bench – Put it up when you need it and fold it away when you need more space.

Premier team
21.04.15
Feb

February's Top Tips

February's Top Tips

February is the start of a busy growing season for a polytunnel gardener, as the climate inside a polytunnel can be a few weeks ahead of the great outdoors and the time to start sowing summer crops has arrived.

Although the weather in February can be bitterly cold and windy, and heavy snowfall and frost are not uncommon, the temperature inside a polytunnel will be on the rise as the sun is warmer and daylight hours are getting longer.

KEEP AN EYE on the soil temperature – Although this can be on the rise this month, February can bring air temperatures low enough to freeze plants even under cover.

TIDY UP overwintering crops – Remove weeds and dead or diseased leaves, and keep a lookout for slugs and caterpillars. Some overwintering crops, such as peas and broad beans, will soon need extra support from canes and strings. Crop Bars are great for supporting canes.

Take advantage of this time between winter and summer crops to PREPARE the polytunnel beds and borders. Keep the soil fed with compost.

Some serious SEED SOWING can start this month. Plants such as tomatoes, peppers and melons benefit from a long growing season and, if started off in February, these plants will be able to take full advantage of a hot May and June. Many seeds benefit from being started off in pots or modules in a heated propagator or on a warm, light windowsill. Try using a Polythene Cloche inside your polytunnel to act as ‘double glazing’, keeping the frost off and saving on heating costs. You can sow hardier crops straight into the polytunnel borders, such as carrots and rocket.

A polytunnel can also be put to GOOD USE by raising hardy outdoor crops a few weeks before they go outside. These sowings will thrive with the extra protection and warmth that a polytunnel provides, putting them ahead in the growing game.

Premier team
21.04.15
Mar

March's Top Tips

March's Top Tips

A polytunnel is the most useful tool for putting you in control of nature, helping to extend the growing season at both ends of the year. It is no surprise therefore that March is a busy month for the polytunnel gardener as you look forward to a great growing season and some delicious summer crops. The polytunnel may resemble a plant nursery at this time of year, with young plants and seedlings needing a lot of care and attention, so to help you prepare for the year ahead check out our handy hints and tips for March.

CLEAR and prepare beds within the tunnel in readiness for summer crops.

ORDER tender plants if you are not growing them from seed. Contact seed companies, many of who supply plants of tender crops, or visit your local garden centre.

PRICK OUT or pot on seedlings as soon as they are ready to keep them growing steadily. Be careful not to let them become root bound, overcrowded or starved of nutrients so as to not lose the precious advantage gained by early sowing.

CHECK watering and ventilation regularly, as the weather begins to improve and feel Spring-like.

START FEEDING tender herbs and fruit kept in pots as the weather warms up. Give them a regular liquid feed, or use nutrient-rich compost or slow-release fertilizer.

KEEP your soil healthy inside the polytunnel by rotating crops or using green manures to avoid the soil becoming dry and lifeless between crops.

COVER and protect vulnerable crops on frosty nights – Consider covering the crops with a blanket, buddle wrap, or even sheets of newspaper! Why not use a Polythene Cloche inside the polytunnel – This acts as ‘double glazing’ for your polytunnel, providing extra frost protection for vulnerable first shoots and young crops, and saving on heating costs.

Premier team
21.04.15
Apr

April's Top Tips

April's Top Tips

Transport your garden a few hundred miles south by growing under cover this month.

CLEAR old overwintered crops to make way for summer plantings.

The planting and growing season begins early in a polytunnel, because we can never be too sure what the weather may do this month, be sure to PROTECT tender plants on cold nights with cloches or fleece (or even newspaper, like some of the pros do!)

Enough about cold nights, let’s think about warm days! Temperatures can soar under cover in Spring, so it is important to VENTILATE the polytunnel by opening doors and ventilation screens on warm days as daylight hours are longer and sunshine levels are increasing.

WATER carefully and keep on top of weeding and staking.

Use fresh COMPOST to beef up the soil in the polytunnel borders ready for planting out as the weather warms up.

MOVE tomato seedlings into larger containers whenever the roots reach the outside of the pot to give them more space.

PINCH OUT the tips of chilli plants to encourage bushy growth and more fruits over the growing season.

WATCH OUT for greenfly and other pests, especially on plants received from commercial companies or fellow gardeners. If possible, for the next couple of weeks keep these plants separate from the plants you have tended and raised yourself. Tip out potted plants occasionally and check for grubs that might have settled among the roots.

FEED strawberry plants (in pots) and help flowers to set by pollinating by hand – moving the pollen from flower to flower by hand or with a soft brush.

Premier team
21.04.15
May

May's Top Tips

May's Top Tips

A polytunnel really comes into its own in May, with young plants jostling for attention and space, making it a busy time for the polytunnel gardener. To help you keep on top of things and make the most of your polytunnel this month, have a read of our hints and tips for May.

WATER, WATER, WATER. Check pots and growing bags daily, even if you have an automatic irrigation system. Most plants do best if the compost is kept moist at all times.

VENTILATE the polytunnel and DAMP everything down on hot days to maintain the best conditions.

INSTALL supports in the polytunnel for plants such as tomatoes, melons, and cucumbers.

SUPPORT tomatoes with strings or canes, and PINCH OUT sideshoots.

THIN OUT and TIE IN vines so that they don’t touch the polytunnel cover.

PATROL the polytunnel daily, looking out for pests, especially red spider mite.

EAT ripe strawberries!

Premier team
21.04.15
Jun

June's Top Tips

June's Top Tips

June can be the hottest, sunniest, and often the driest month of the year. Daylight hours are long and things can get very hot in the polytunnel, meaning that the best times of the day to work inside the polytunnel are mornings and evenings. However, with the UK weather being what it is, on wet days the polytunnel ensures you can continue to work undercover – there is nothing more tranquil than listening to the rain clatter down on your polytunnel while you relax and tend your plants inside.

SPF! You can still get a suntan while working inside a polytunnel that is covered with a standard or Thermal Anti Drip polythene cover, so don’t forget the suntan cream!

WATER regularly and carefully. Check the soil regularly to ensure it is not too dry and not too waterlogged – Overwatering can be just as damaging as drought. The soil should just be moist.

MULCH, using hay or grass cuttings for example, to keep the soil moist.

If you are off on your summer holiday this month, there is no need to worry about whether or not your friend, neighbour, or family member will remember to water the plants that you have tended and nurtured – Our Premier Irrigation kit (available for all sizes of polytunnels) includes a top of the range Galcon battery operated tap timer, doing away with the need for a watering can or even the presence of a person, meaning that you can go on holiday safe in the knowledge that your crops will still regularly receive the right amount of water.

Anyone who has stood inside a polytunnel on a sunny day will know how hot it can get under a polythene cover. VENTILATE the polytunnel early on sunny days – Open the doors and side vents to give valuable air circulation.

Provide SHADE and keep temperatures down under the hot midday sun by using a net polytunnel cover. Our green 47% shade net is ideal to be used on a polytunnel with or without a polythene cover in place. Used on its own, a net cover provides shade, full ventilation, significant reduction in wind speeds, and still allows rainwater to filter through to the plants. Placed over a polytunnel with a polythene cover in place, the net provides shade and significantly reduces the temperature inside.

Alternatively, add SHADE and reduce temperatures by tying shade net above head height on the inside of the polytunnel – Try using cable ties to secure the net to hoops, ridge bars, or Crop Bars.

NIP OUT or tie in side shoots and new growth to prevent overcrowding inside the tunnel.

FEED plants in pots and grow bags, such as tomatoes and cucumbers.

POLLINATE melons and THIN grapes.

WATCH OUT for undercover diseases and pests, such as whitefly and red spider mite.

Premier team
21.04.15
Jul

July's Top Tips

July's Top Tips

July is the time to enjoy the tastes of summer as your kitchen should be full to the brim with fresh fruit and vegetables straight from your polytunnel.

July has a reputation for being the wettest month of summer, but high pressure can also result in a heat wave for at least part of the month.

VENTILATION is vital in the summer months. You can avoid a lot of problems, such as moulds or wilting plants, if you maintain good ventilation in the polytunnel during summer. Leave doors and vent screens open on hot, sunny days for maximum air movement. It may be worthwhile leaving doors and vent screens open overnight if the sun is up before you. If you need to reduce wind chill or keep unwanted visitors, such as cats, rabbits, and birds, at bay while the doors are open, hang windbreak/shade net or anti bird net across the door openings.

DAMP paths inside the polytunnel and MIST overhead on hot days. This will help to keep the atmosphere humid and discourage red spider mite.

WATER regularly. Careful watering is essential at this time of year. It is recommended that you water your polytunnel plants in the evening or early morning, rather than during the heat of the day, as this reduces the amount of water lost through evaporation. Plants in pots and containers may need watering daily, unless they are stood in a tray of water. Why not make use of the July rainfall and collect rainwater in water butts.

If you are going on holiday in July, our Premier Irrigation kit is the ideal way of ensuring you can go on holiday safe in the knowledge that the plants you have tended and nurtured will still regularly receive the right amount of water. A Premier Irrigation kit is an overhead irrigation system, which is supplied in single, twin or triple line specifications, and includes an adjustable pressure regulator for those areas where water pressure is high. This kit also includes a tap timer, doing away with the need for a watering can or even the presence of a person!

REMOVE any unwanted and infected foliage, and keep bulky foliage TRIMMED, ensuring that light and fresh air can reach all areas of the polytunnel.

PATROL the polytunnel daily, ensuring you are in CONTROL of any pests and diseases.

FEED fruiting crops, such as tomatoes, cucumbers, melons, peppers, and aubergines, with a high-potash liquid feed.

CLEAR early summer crops and start SOWING for autumn and winter crops.

Premier team
21.04.15
Aug

August's Top Tips

August's Top Tips

August brings an abundance of delicious, fresh and healthy, home grown produce, together with a great sense of achievement for the polytunnel gardener. Heat-loving crops, such as tomatoes, pepper, corn cobs, cucumbers, aubergines, melons and many more quickly fill even the largest of baskets this month, so be ready to pick, pickle and freeze! Friends and family, neighbours and work colleagues will be happy to relieve you of any surplus fruit and veg!

You may have more produce than you know what to do with, but it is important to KEEP PICKING so that plants keep producing new fruit well into the autumn.

Don’t forget the two important rules of polytunnel growing during the summer months:

1. Keep VENTILATION to a maximum and allow air to circulate between the plants. Overheating can kill plants. Polytunnel doors should be opened as soon as the sun shines.

 2. Keep WATERING regularly and carefully. If the atmosphere is very dry, mist overhead and hose down paths.

CUT BACK foliage and REMOVE any unwanted, diseased or damaged, yellowing foliage as soon as they appear to help prevent the spread of fungal diseases and allow air to move more freely throughout the polytunnel.

Keep FEEDING ripening crops and plants in pots regularly. Switch to high-potash fertilisers to encourage tomatoes, melons, and cucumbers to continue to fruit well.

POT UP strawberries for next year’s undercover crop.

PRUNE fan-trained peaches and nectarines.

PINCH OUT the tops of tomato plants when they have reached the required height, removing the entire stem to just above the topmost pair of leaves. This helps to concentrate the plant’s energy on ripening tomatoes, rather than getting taller. Repeat this process every week or so, when needed.

STAKE peppers and aubergines to help support the plants, keep them upright, and keep them off the ground where they are vulnerable to pests or rotting.

It may only be August, but in the polytunnel it is not too early to be thinking about winter; PREPARE beds for overwintering crops – CLEAR AWAY any spent plants and rejuvenate the soil and beds with fresh compost, and keep SOWING autumn and winter crops.

Premier team
21.04.15
Sep

September's Top Tips

September's Top Tips

Start CLEARING summer crops – Be ruthless and pull up any plants that are no longer at their best, thus making valuable space for winter crops.

In wet weather, USE SPARE SPACE inside the polytunnel for drying outdoor crops.

PRESERVE tender herbs, such as basil, lemon verbena, and sweet marjoram (which start to deteriorate in damper, cooler weather). This will help to capture the last of their delicious summer flavour.

SHUT doors and vents on cold nights (which may start to become frosty before the month is out), but ensure VENTILATION is good during warm, and even cooler, days. Good ventilation in the polytunnel aids winter crops and helps to minimise condensation which can lead to an increased risk of fungal diseases.

PULL UP weeds and REMOVE debris, such as pots, canes, and rubbish that could be hiding diseases and pests, such as red spider mites, aphids, and whiteflies, that could be carried over into your winter crops.

As the weather gets cooler and growth slows down, REDUCE the amount of watering inside your polytunnel, ensuring that your crops are not left to sit in waterlogged, cold soil. Plants such as tomatoes, cucumbers, and melons may still have lots of fruit, but their growth is slowing down and they are using less water. If you keep giving them the same amount of water, they will quickly become waterlogged which could spoil the rest of your crop.

DON’T let cucumbers get too cold as the temperature drops. During colder days and every night, try to keep them as warm as possible. Give them a weekly dose of liquid tomato feed and they should remain productive right up to the first frosts.

REMOVE lower leaves from tomatoes as they turn yellow, allowing more sunlight to reach the ripening tomatoes. September is the time to HARVEST tomatoes, but some tomato plants can continue cropping into October – But don’t hesitate to pull out any sickly plants.

In September the days start getting shorter and the sun gets lower, so now is the time to REMOVE any summer shading to ensure your plants can make the most of the remaining summer weather.

WASH OFF any dirt from the polytunnel cover, in readiness for allowing more sunlight into the polytunnel as daylight hours get shorter during the winter months.

REPAIR any tears in your polytunnel cover before the winds get higher. Once repaired with polytunnel repair tape, there is no reason why the cover will not last its full term.

Premier team
13.12.18
Oct

October's Top Tips

October's Top Tips

Although work in the polytunnel starts to wind down in October, there are still plenty of jobs to do over the autumn and winter months to keep ahead of the game.

KEEP HARVESTING – Expert October harvesting tips, ensuring you can continue to enjoy your own delicious home grown produce this month, are available in ‘The Polytunnel Book – Fruit and Vegetables All Year Round’.

TIDY UP – Get the polytunnel ready for next year’s growing season – Think “clean and clear!” Clear expendable summer plants that have finished cropping or are showing signs of disease, clear any debris, begin washing used pots and scrubbing staging and benches, sweep pathways, and clean and repair the polythene cover. (Tidying a polytunnel ready for the coming year can be a big task, so don’t worry if you don’t get everything done this month).

KEEP DOORS SHUT – Close doors and vents early (as soon as the sun disappears from the plot) and keep them closed when it is cold and windy. This will help to protect the plants that you have nurtured during the spring and summer months from frost on the cold nights that are to come.

KEEP PLANTS WARM – Extend the growing season by keeping plants warm when temperatures drop. Many people use fleece and even newspaper to cover their crops in cold and frosty weather.

Premier Polytunnels Tip! A polythene cloche is ideal for ‘double glazing’ your polytunnel. Using a polythene cloche inside your polytunnel during the colder months gives your plants extra protection from the cold British winters, keeping the frost off your crops and saving on heating costs.

WATER CAREFULLY – Crops need much less water now that plant growth is slower, therefore watering should be reduced to a minimum this month.

Premier team
21.04.15
Nov

November's Top Tips

November's Top Tips

November has arrived and while many gardeners will soon be thinking of retiring their polytunnel for the winter, others will be determined to get the most out of their undercover plot for a little while longer.

If you are planning on putting in a few hours in your polytunnel this month, here are some handy hints and tips to help see you and your crops through November.

PICK off yellowing and dead leaves and continue with the big TIDY UP started in October.

SORT plant labels ready for next year – a job always better to be done inside the comfort of your polytunnel, rather than out in the cold, wet borders of the garden or allotment!

ORDER seeds ready for next year; Sort through seed catalogues and place your order in advance to ensure you do not miss out and that your new seeds arrive in good time. Any seeds you still have should keep over winter if they are stored in a cool, dry, airtight container, although parsnip and parsley are best bought fresh.

CLEAN the polytunnel cover to remove any grimy green coating and dirt. The clocks have gone back and daylight hours are shorter, so cleaning the polythene will let more light into the tunnel during the dark winter months. Try Algon for a safe and effective way of cleaning your polytunnel cover or greenhouse glass.

SAVE on heating bills and insulate your polytunnel with bubble wrap before the cold winter weather really sets in. Close doors and vents, and cover any ventilation net with spare polythene or bubble wrap.

Premier team
13.12.18
Dec

December's Top Tips

December's Top Tips

With colder weather, shorter days and excitement of the festive season upon us, it is not uncommon for little work to be done inside the polytunnel this month. Many polytunnel gardeners will be clearing the last of the year’s crops and preparing the beds for the next busy growing season, while others will be enjoying some winter gardening.

USE a Polythene Cloche inside your polytunnel to act as ‘double glazing’ during the winter months, keeping the frost off your crops and saving on heating costs.

Do not let too much snow sit on the roof of your polytunnel. REMOVE excess snow by tapping on the sides of the polytunnel cover and on the roof inside if you can reach. Use a soft brush to knock snow from the harder to reach areas.

INSULATE your polytunnel by covering ventilation and doors with bubble wrap.

BRING IN pots from outside to protect from cold winds, waterlogging, and very low temperatures.

WATER CAREFULLY – Normal advice for December is to keep watering to a minimum as damp soil and foliage encourages fungal diseases. Soil may look dry, but check just below surface with your finger or a trowel. Plants in pots are likely to need more water.

ORDER SEEDS – Send off for seed catalogues and consider what you need for next year. Think about what worked well for you this year and what didn’t do quite as well, and put in place your plan of action for next year.

WASH pots to avoid diseases being carried through to the next busy growing season.

Premier team
21.04.15

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