8 Reasons to Buy a Greenhouse
Expert Advice

A Greenhouse brings an entirely new dimension to any garden. It will make your gardening dreams a practical reality and continue to give you satisfaction year after year. Glass enables you to raise your own seedlings, create colorful floral displays, and to produce delicious food items – from tomatoes or peppers to grapes and melons. Not to mention being a handsome focal point as an object of beauty and pride. Here are eight reasons to buy a greenhouse from our friends at Hartley Botanic.

1. Grow Your Own Variety of Edibles

A wide range of tender vegetables can be raised in your greenhouse. Your difficult decision will not be what to grow, but what to leave out, since space is always limited, and you’ll have some hard choices to make. Remember, though, that Greenhouse crops are ‘high maintenance’ and, even with automatic watering, will need daily attention.

Tomatoes: Nothing tastes quite so delicious as a fresh-picked, home-grown tomatoes. When selecting varieties to grow at home, go for those with the best flavor, since yield is less important. Even with modest croppers, if you grow your plants well, you’ll have a surplus each year. There are hundreds of varieties, in a surprising range of sizes, shapes, flavours and colours.

Peppers, eggplants, and other related crops: Chilies can be grown over two or three years and will develop into attractive, colourful bushes. As summer patio plants, they are useful and beautiful, but they’ll need returning to the greenhouse for winter to be kept frost-free. Chilies are best started from seed, sown either in early spring or with heat in autumn for spring production.

Peppers and eggplants are grown in similar conditions to tomatoes. They are slightly more prone to rot diseases, however, and fruit failing to set when temperatures differ sharply between day and night. Shading the plants may be advisable during the warmest part of summer – but that is likely to benefit other greenhouse plants as well.

Cucumbers: Second in popularity, after tomatoes, cucumbers are a little more demanding but still not difficult to grow. If looked after, and regularly cropped, cucumber plants will provide a succession of good fruits, even when grown in an 8-inch pot.

 Fresh greens: Lettuce or arugula also grows speedily in autumn and winter but will be less dense and more drawn up or ‘leggy’ than if started in spring or summer.  Most seed companies also produce mixes of ‘cut and come again’ salad greens. These can be harvested a little at a time, and if sown at regular intervals, will produce greenery all year round.

Herbs: While many herbs are hardy and grown in the open garden, some herbs from subtropical regions perform more reliably in the warmer, more humid conditions of a Greenhouse. Many others, such as sage, rosemary and thyme can also be grown in pots in a frost-free Greenhouse over winter to provide you with a continuous supply of aromatic leaves.

Grapevines and Other Greenhouse Fruit: In the days of the great Victorian estates, Glasshouses were used to produce all manner of off-season and exotic fruits, from figs, peaches, and apricots to bunches of big, luscious grapes and even pineapples. A small Greenhouse space prohibits such extravagance, but you can grow several high-value fruit crops and still leave plenty of room for other plants.

Grapes: The quality of grapes grown under glass can often be greatly superior to any harvested outdoors. Extra close attention given to your vine will reward you with superb grapes on large, well-shaped bunches. Ideally, the vine rootstock is planted outside, with the main stem fed through into the greenhouse.

Wall fruits: Peaches, nectarines, apricots, and figs are the best ones to try if you have the wall area. In limited space, dwarf trees can be grown in large pots to produce more modest crops. In summer, such little trees can be lined up or arranged outside. Be sure to look up pruning techniques – they are too complex to go into in detail here.

 Citrus: Producing your own crops of lemons, kumquats or calamondin oranges is a real possibility under glass, but the sweet-scented flowers on these evergreen trees and shrubs are reward enough. 

2. Grow Plants from Scratch

Use your greenhouse, not only for growing existing plants, but also for obtaining a great many new ones. One way to do this is by propagation using cuttings. A greenhouse plus a heated propagator will give you control over growing conditions enabling you to grow the most challenging plants from seed. You can set temperatures within the desired range, allocate precisely the right amount of water and ventilation to handle seeds in hygienic conditions while sustaining good plant health. You can bring the sowing dates of tender plants forward, even starting them off in the depths of winter.

3. Beautiful Bedding Plants Throughout the Year

Raising and growing on your own bedding plants is one of the great benefits of owning a greenhouse. You will be able to grow as much as you want, which you can then tailor to suit your circumstances and needs. It also offers the opportunity to try out varieties, both new and old, which may be unavailable from local stockists. Plan creative displays of colourful flowers and foliage.

4. Greenhouse Ornamentals Create a Stunning Display

Most people like their greenhouse to look alluring and to have floral interest, particularly during the winter when the outdoor garden becomes low key. For winter floral displays, and with minimal heat, you can grow cyclamen from seed as well as greenhouse primrose, old fashioned pot cineraria or the updated varieties called Senetti. Spring provides opportunities for potted, large-flowered columbine, butterfly flower, trailing violas and, as the days lengthen, a vast range of summer display plants. Cape primrose provide floral abundance, New Guinea impatiens make big, bold statements, and you can utilize upper shelves with such trailing plants as goldfish plant and star of India to notch up the fragrance by including heliotrope.

5. Out of Season Flowers

One of the delights of having a greenhouse is to produce out-of-season flowers. By providing extra warmth, plants which are normally dormant during winter can be ‘woken early’ and will look their best several months ahead of those grown naturally outdoors.

Bulbs for winter display: Popular spring bulbs or corms, including tulip, narcissus, hyacinth, crocus, florists’ anemone, and Dutch iris can be forced into flower from midwinter onwards. Some, such as hyacinth, are often available as ‘prepared’ bulbs, i.e., they have been treated to simulate an artificial winter and will therefore spring into growth as soon as planted. Bulbs grown in borders or growing bags for cut flowers can be planted densely to maximise the crop. Forcing provides an excellent out-of-season display, but exhausts the bulbs, which should be discarded after use.

 Tender bulbs: Non-hardy bulbs such as spider lily, forest lily, bugle lily can all be safely grown in a greenhouse. Some, such amaryllis and the startling red Aztec lily will flower under protection in spring with others that can be grown on in warmth until early summer, and then planted outdoors a few weeks before they are due to flower.

6. Cut Flowers for Winter and Spring

If you have a greenhouse bed and like to grow summer food crops, a good winter use for the vacant space is to raise cut flowers. Especially bred strains of snapdragon and ten-week stock, for example, will produce superb spikes for cutting. Freesia cultivars can be grown for display or cutting and flower naturally in late winter and thrive in a cool greenhouse. Also try primrose, bells of Ireland and for later in the year, prairie gentian. All these plants are easy to grow and will give impressive results.

7. Grow Your Own Vegetables Early

A greenhouse is the stepping-off point for outdoor vegetable production. As well as raising tender crops such as zucchini and outdoor cucumbers, you can kick-start runner beans, brassicas, (like broccoli, cabbage, and kale,) and root crops as carrots and beets. And you can use a little spare staging to “chit” seed potatoes, i.e., expose them to light and warmth to encourage their shoots to begin growth prior to planting.

If kitchen garden produce is started into growth in late winter or early spring, the first harvest will be weeks ahead of crops raised entirely outdoors.  Your greenhouse will enable you to significantly extend the productive year. With strawberries, for example, if you use specially designed containers with planting pockets down their sides, the plants could produce fruit in May and again in November.

Meanwhile, your maincrop strawberries outside will crop from late June to early August. Summer broccoli, sown in January, may be in production by late June and, if you sow your first runner beans in February under glass and plant them out in May, they’ll crop from late June to September. Meanwhile, bean seed sown outside in late June will crop from late August to November, until deteriorating weather brings productivity to a close. 

8. Build an Amazing Collection of Exotics

In a greenhouse, exotic growing need not be limited to edibles. If you are a keen gardener, the chances are that you have your eye on a few extra special plants that you’ve always wanted to grow. You might not need a greenhouse to keep them the whole year around, but it might be just the right environment to take cuttings, grow them from seed or just to over winter them. Why not try your hand at stunning orchids in jewel-like colours, exotic flowers such as passionflower or even a selection of architecturally interesting carnivorous plants? The world really is your growing oyster when you buy a greenhouse.