Greenhouse Growing

Pippa Greenwood explains the wonders of having a greenhouse and shares some timely tips and advice

RunnerBeanSeedlings
Use the greenhouse warmth to sow and grow runner beans Image: Martin Mulchinock

A greenhouse could be defined as a gorgeous growing opportunity and if you don’t already have one I can only say that you should try to squeeze one in to your garden somewhere. It is an investment but perhaps you could persuade friends and family to give contributions to your greenhouse fund for the next few birthdays and Christmases?

Greenhouse benefits

When I got my first one I couldn’t believe just how brilliant it was:

A greenhouse allows you to extend the growing season at both ends, to grow a wider range of crops and ornamentals, to out-wit the unpredictable British weather ( to a good extent!) and of course to raise from seed a massive selection plants which you can then also grow on with ease.

RunnerBeanSeedlings
Use the greenhouse warmth to sow and grow runner beans
Image: Martin Mulchinock

I have to confess that I also use my greenhouse as a hiding place when life gets too fraught! If you’re buying a new greenhouse try to get one a bit bigger than you think you need because greenhouse growing is addictive……as are the delicious early and late crops of tomatoes, aubergines, peppers, okra, melons, cucumbers that you can enjoy!

Making your greenhouse useful

So how can you make it as useful a place as possible and how can you ensure that any plants growing in your greenhouse are as ‘happy’ as possible?

Greenhouse inside
Make the most of greenhouse space with staging and shelves
Image:Jean Vernon
  • Remember that light levels vary within a greenhouse – so if for instance conditions are a bit gloomy and you want to avoid seedlings or plants becoming too leggy (etiolated or drawn), then position trays, cells and pots higher up and never at ground level or anywhere that staging or other plants might cause shading.
  • Temperatures also tend to be greater higher up within the greenhouse, but be wary of the potential draughts from roof vents or windows, especially early and late in the growing season and towards the evening.
  • In the warmer weather greenhouse temperatures can build up too high if you don’t take precautions. Even a hot spell in April can prove disastrous on occasion. Adequate ventilation is vital so make sure that you use all available vents and windows and even the door so that you get a through flow of cooling air. All too often there are not enough windows and vents so I’ve been known to (very carefully) remove a pane or two of glazing in the warmest weather. Erecting or applying greenhouse shading may also be necessary but I suggest that if you’re after growing the real-sun-lovers such as aubergines and peppers,
    GraftedAubergine
    Grow high value greenhouse crops like aubergines
    Greenhouse Peppers

    you only shade part of the greenhouse and leave an area in the sunniest part un-shaded so that these crops get the maximum possible amount of sunshine (and so provide you with the best possible harvest!)

  • The lovely warm, sheltered conditions can mean more problems with pests so when you’re greenhouse growing do take extra care to do some pests and disease patrols. Pinning or taping micromesh over windows can dramatically reduce problems with flying pests including greenfly, butterflies and moths. You can cut it to size to fit your windows and vents and then re-use it year after year. There is a fantastic range of biological controls available for greenhouse pests so, if things do go wrong don’t forget that there’s no need to resort to chemicals if you’re under attack from pests such as glasshouse white fly, red spider mite, mealy bug or aphids (you can find out more and order these from www.pippagreenwood.com/products/protect-your-crops – we get them posted out to you, first class, very promptly so that a small problem shouldn’t become a nightmare!
Pippa Greenwood

About Pippa Greenwood

Pippa’s gardening passions include grow your own and the things gardeners hate most – pests and diseases! She gives many gardening talks and worked for the RHS for years, spent 13 years as a presenter on BBC Gardeners’ World and since 1995 has been a regular panellist on BBC Radio 4’s Gardeners’ Question Time. She was also the gardening advisor for the murder-mystery series, Rosemary & Thyme. Vist Pippa’s website www.pippagreenwood.com for gorgeous vegetable plants with advice from Pippa, pest controls and more
@PippaGreenwood
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