14:50 - 11 October 2010
Take time to clean out your greenhouse in the autumn, it’s the best time to do it and will save you hours of hassle when the growing season resumes in spring. What’s more it will also deal with any bugs and diseases lurking in the corners that have taken advantage of the protected greenhouse environment. By reducing their numbers or eliminating them entirely you are giving any plants you intend to protect over the winter a far better chance of survival and also reducing potential problems for the season ahead.
By autumn your plants will have filled the greenhouse right up to the eaves and as most cropping plants such as tomatoes, aubergines, peppers, cucumbers are tender and some are annuals, their useful life is over and it’s time to tidy up. Choose a warm, sunny, autumn day so that you can place plants outside while you clear up inside or have a cold frame where you can place susceptible plants for a few hours, or if they are really tender then bring them indoors while you work.
Plants
Cut the main stems off at the base and remove the pots of spent compost, these can be added to the compost heap. It’s then a matter of unravelling the fading but previously rampant plant growth that has wrapped around plant supports, greenhouse eaves and greenhouse structure. Some plants will have really hung on to support their heavy fruit and may need cutting away. Be sure to remove every last leaf and tendril as they may be harbouring pests or disease. Any that are obviously diseased should be disposed of very carefully, ideally by burning, but if this is not possible, wrap them in paper and add them to your green waste bin. The rest can be chopped up and added to the compost bin.
Stack the used pots up outside ready for washing and readying for next season’s plants.
Any plants that are still growing for winter crops and overwintering should be checked over carefully. Lift up each pot and check underneath for sheltering slugs and eggs and remove them.
Tender plants such as geraniums and fuchsias should be tidied up, Remove any spent flowers and dead leaves and prune back any straggly growth. Weed the pots if necessary and wipe them over removing any dirt.
Greenhouse
Once the plants are safely and securely outside clear out as much as possible from the greenhouse. Ideally it should be emptied completely so that you can carry out a thorough cleaning process. Remove the benches and staging and sweep the floor and paths removing any plant debris, broken pots and anything else that shouldn’t be there. Using a stiff brush and a sponge wash over all the surfaces, the greenhouse framework, walls and staging that can’t be removed using a dedicated greenhouse cleaner. Don’t be tempted to use something in the kitchen cupboard, you need a horticultural cleaner that will deal with greenhouse and garden pests, but won’t leave a residue that may harm your plants. Pay particular attention to cracks and crevices, as this is where many pests will shelter. Be careful to protect electrical sockets before you start. Don’t forget to thoroughly clean any staging and benches taken outside.
Make sure the greenhouse cleaner has time to work, this may mean leaving it for a few hours and then wash down with a hose. Now you need to let the greenhouse dry out which is why it’s a good idea to choose a sunny day. Open the windows and the vents to let the air through. Once it is all dry, sort through everything and only put back the essential things. Use the opportunity to rearrange the greenhouse so that the space is used to the best advantage. Keep an eye out for the tell tale signs of rodents in the glasshouse, some will move into the greenhouse during the autumn to shelter from the weather. Install an ultrasonic device if you have a power point and use your preferred method of control.
Outside
Don’t neglect cleaning the outside of the greenhouse. Keeping the glass free of algae and debris becomes more important as the light levels drop, so that the plants can benefit from all the available light. Wash them over carefully using a suitable cleaner for algae.
Clean out the gutters to make sure they are running freely and attend to any damage, rust or problems with the framework. If you have waterbutts attached to the guttering ensure that the rainwater is able to run into them freely. If you don’t have waterbutts then consider installing some to capture the natural rainwater.
Timber framed greenhouses, especially those made from soft wood, should receive special attention especially anywhere that the wood is perishing. Repair any broken glass and replace any rotten timber or broken glazing bars before they cause damage to the greenhouse structure.
