Historic Greenhouse and Glasshouse manufacturer Hartley Botanic has been helping its customers make the most out of their beautiful, handmade structures for over 80 years. Founded in 1938, the company is one of Britain’s oldest and most trusted Greenhouse manufacturers and its entire product range is endorsed by the Royal Horticultural Society. Here, the Lancashire-based company has worked with gardening writer Matthew Biggs to share some ways Greenhouse owners can get ready for spring.
Even with the lure of spring just a few weeks away, don’t be tempted to discard all your winter insulation. Any time from February to April (and up until early June, further north) can still bring low temperatures and frost, which means tender plants will be at risk. If you’ve already insulated your Greenhouse with bubble wrap polythene over winter, you can remove some, if it is practical, on warmer days and reinstate it in the evenings. Removing some insulation will also allow more light in to the plants below.
Make use of the warmer, sunnier days to give your Greenhouse a much-needed tidy up. Continue to remove weeds and debris and make sure you’ve got enough clean seed trays and pots in a range of sizes ready for lots of sowing by washing them in water with a drop of eco-friendly disinfectant, then rinse thoroughly. Choose warmer days to ventilate your Greenhouse to reduce the risk of botrytis, or grey mould, closing the vents by mid-afternoon, before temperatures drop.
Before you get stuck in with your sowing, it’s worth spending a bit of time getting your compost ready. Larger seeds, like peas, can be grown in a peat free multipurpose compost, while smaller seeds like lettuce and tomatoes can be grown in similar seed compost. Put your bags of peat-free compost in your Greenhouse for 24 hours to warm up, or fill your pots and trays and then warm them up in a propagator. It’s also worth warming up a watering can of tap water in the Greenhouse too. Tap water is preferable as the chlorine acts as a fungicide.
Chillies, peppers and aubergines can take a long time to grow in the UK from seed to fruiting. If yours haven’t ripened by early to mid-autumn, then you’ve probably sown them too late. Ideally aim to sow them in the third week of February. Failing that, mid-March is fine but the first week of April is your absolute deadline. They’ll need to be kept light, warm and at a constant temperature of 18-21C to germinate. If this is going to be a struggle, then you can always buy younger ‘plug’ plants later in the year.PERFECTING CELERIAC
Raw in salads or cooked in stews, celeriac is a tasty root that’s making a bit of a comeback. February and March are good months to start sowing in trays under glass at temperatures between 16º and 18ºC degrees. As soon as they are large enough to handle, transplant into trays 5cm apart and ‘harden off’ once the danger of frost has passed. Grow bolting resistant varieties like ‘Prinz’ or ‘Alabaster’ which cope better with erratic growing conditions.DORMANT PLANTS
Late February and early March is a good time to move dormant plants like heliotrope and fuchsias up onto the benches in a warm area in your Greenhouse. Think about a nice spot in your Greenhouse, where the temperature is around a constant 10ºC, or put them in a heated propagator. Increase the amount of water as soon as growth starts to show.BRING ON THE BEGONIAS
Having spent winter safely stored and dry, mid to late February is the ideal time to start off beautiful tuberous begonias. Put them into a tray of multipurpose compost, moisten with tepid water and place them into a heated propagator at around 20ºC. Once the shoots are around 2cm in length, pot them into 15cm pots and, as the roots reach the sides, transfer them into larger containers. Remember to plant begonia corms the concave side up – depression on top, slightly above or level with the surface of the compost. Water around the corm, with tepid water; be careful not to let water sit in the corm as this could lead to rotting.EARLY POTATOES
February is also a good time to think about planting some very early potatoes. Re-use some large compost bags, turn them inside out, roll down the sides and punch holes in the bottom for drainage. Fill the bags with a good peat free compost and sow Swift, International Kidney (or Jersey Royals), Rocket or Belle de Fontenay, topped up by another 15cm. Keep them warm, in a bright, sunny spot and frost free. With regular watering, shoots will start to appear. Once they’re around 15cm in length, roll the sleeves of the compost bag back up and fill with the same peat free compost.