Give the Greenhouse a Good Clean in November

My greenhouse looks twice its normal size now that the tomato, aubergine and pepper
plants have been removed – and what a brilliant season it has been for all three. As I write
this at the end of October, I am still picking sweet peas in the garden and no sign of a frost
yet. It is ridiculously warm.

And these higher-than-average temperatures should sound a note of warning because the
greenhouse will act as a lovely incubator for all sorts of unwanted pests and diseases. So, it
is best to clean up now and make sure they are not there to attack any plants brought inside
to over winter.

The inside glass should be cleaned with a very mild bleach solution. Always wear rubber
gloves and protects the head and eyes. This will easily remove the build up of dirt and
potential homes for all sorts of pests. Give the framework, shelves and staging a thorough
clean with the same solution. Make sure you complete this before you bring in the over
wintering pots and containers.

Repair any cracked or broken glass. It is also a good time to oil all hinges, ventilators and
door runners. Check the staging and shelving to make sure everything is secure and tighten
any loose screws or bolts. If you have a wooden greenhouse, now is the time to give the
interior a coat of wood preservative.

Guttering to collect rainwater needs a thorough clean out to remove any moss or leaf build
up. Also check drainpipes leading to water butts or drains. Leaves will quickly block these
and cause flooding.

Finally, remove anything that is not essential. A greenhouse is not a storage unit and non-
essential items left over the winter will rapidly become home to slugs, snails and other
unwanted lodgers.

Before I bring in overwintering containers and pots, I cover the thoroughly weed-free beds
with pallets. This keeps pots etc. off the soil and ensures good drainage. Many of these
plants will house slugs and other pests, so keep a watchful eye out and treat accordingly.
Watering is a difficult task at this time of year. Some plants like geraniums don’t really need
watering after November and will happily die back until spring. More difficult specimens
like lemon and orange plants should only be fed and watered monthly and allowed to dry
out in between. But keep an eye on them and if they look dehydrated, give a small drink.
November is the right time to plant out apricot, nectarine and peach plants against a back
wall. Prune established vines as soon as the leaves have fallen and you can plant new ones.


Good ventilation is important on warm, sunny days. Open the windows and leave the door
ajar, remembering to close up before nightfall. If we are unlucky enough to have a hard
frost, cover more tender plants with horticultural fleece and make sure they are not in any

It won’t be long before the seed planting begins so make sure there is plenty of clear space
on staging to undertake the task and house the trays. Use some of that mild bleach solution
to wash pots and seed trays but don’t store them in the greenhouse. They make lovely
houses for pests.

Finally, after you have given the floor a good sweep and wash over, pull out a chair, sit down
and thumb through your seed catalogue. I love it in my greenhouse on a cold day.

Posted by David in Tips