Today Carol, The Sunday Gardener, gives us detailed greenhouse advice and talks us through the many benefits of having a greenhouse or poly tunnel in the garden. If you’re considering buying a greenhouse, or have just bought one this is the post for you!
Busy In The Greenhouse With The Sunday Gardener
My greenhouse arrived over 10 years ago and I can still remember the excitement of stepping into it for the first time. It seemed so large. The advice, when buying a greenhouse or poly tunnel, is always to buy the largest you have room for and can afford; it’s good advice. A greenhouse is so useful, it’s full all the year round.
In spring there are trays of seedlings, germinated earlier in the year in the warm of the house. If seedlings are left indoors in the warm for too long they can become sappy, which is a bit on the floppy side. Also seedlings will always stretch towards the light which makes them grow leggy. The greenhouse has ideal growing conditions, cooler but frost free, and with 360 degrees of light, there is no need to turn the trays of seedlings and they grow into sturdy little plants. At present there are trays of sweet peas, calendula, nasturtiums, runner and broad beans, lettuces, tomatoes, cucumber, courgettes, herbs, all for summer planting. You can even start early potatoes in large containers or sacks. Second sowings of flowers and veg can be germinated in the greenhouse, and sometimes there is even room for a third sowing.
Greenhouse Winter Warming
And there’s more. At the end of last summer I picked up dozens of tiny perennial plug plants cheap. Too small to plant out and withstand the winter, they have been happy enough in the greenhouse all winter, growing slowly and by late May/early June they will large enough ready to plant out. The protected environment of the greenhouse is ideal for nurturing small plants and I love a bargain.
The greenhouse has been fairly full all winter. In addition to all the plug plants, along one side of the greenhouse is a trestle made of a few bricks and plants, and on which tender plants have overwintered. The shelter of a greenhouse is particularly helpful if you garden in an exposed area. The greenhouse has looked after evergreen Agapanthus, Bay trees, Zantedeschia and Pelargoniums. In exposed areas Dahlia are unlikely to survive in the ground over winter, and the greenhouse is an ideal spot for starting them off.
Greenhouse Advice For Bedding Plants
Bedding plants add colour to our gardens and containers in the summer. The greenhouse is a great place to start off bedding plants, either as seeds, economical plugs or as larger plants. They can be planted up into hanging baskets and grown on in the greenhouse so that they are good sized plants and well rooted when planted out. Often bedding plants have been grown in near perfect conditions in a nursery, and to bring them home from the garden centre to plant outside in a chilly spring or early summer is a bit of shock. A sudden change in temperature can be enough to arrest the plant’s growth which will delay flowering. Providing bedding plants with a spell in the greenhouse gives them time to acclimatise as part of the hardening off process and produces better growth. Our summers are unpredictable and I remember, in my pre-greenhouse days, planting bedding during May and the weather immediately delivered a large dose of hailstones.
All plants which have been raised in a greenhouse will need to be hardened off, that is gradually acclimatised to the less clement conditions outside before planting out permanently. This is because they are not frost hardy. Put the plant trays outside towards the end of May in mild spells, leaving outside for longer and longer periods, then overnight, until the plants are outside all the time at which point they will be ready to plant up.
A Refuge From Pests
The greenhouse can also be used as a rescue home for bedding plants which have been chewed up by slugs. This is a real problem in the summer, and it is hard to keep up with the slugs. The Sunday Gardener has plenty of tips on how to beat the slugs and snails, but sometimes they get the better of us and a single slug can almost destroy a bedding plant. Don’t despair if you find a slimy chewed up plant. Dig it up, re pot it and bring into the safety of the slug free greenhouse. Give it a couple of weeks to recover and all will be well for planting back out. The images below show the “before” and “after” and the plant on the right is well recovered after a spell in the greenhouse.
Growing In The Greenhouse
In late spring it’s time to move out the overwintering plants, which makes space to move in tomatoes and cucumbers. I love home grown tomatoes, but when growing them outside blight is a problem. Tomatoes grown in the greenhouse avoid the blight problem and it is an ideal growing environment. Tomatoes grow well in containers, and I usually grow 6-7 tomato plants along with a couple of cucumbers. The humble cucumber is so much better when home grown; sweet, crunchy and fresh. Cucumber sold in the supermarkets have often been hanging around for a couple of weeks or more.
The greenhouse helps to prolong the growing season, but generally, depending on the type of summer we are experiencing, by late October the tomatoes, cucumbers, and greenhouse veg are finished. I cut off the last vines from the tomatoes and bring indoors to ripen, and give the greenhouse a good clean. It is then time for the cycle to start again, build the trestle and bring in the tender plants for over wintering.
The greenhouse is always full and busy. Except for those quiet moments when I sit down, have a cup of tea and just enjoy it.
If this excellent greenhouse advice has piqued your interest in more expert posts have a read of Expert Rose Care With Jenny Williams.