Forum home Problem solving

How to stop compost going damp in an unheated greenhouse.

rholden_82rholden_82 Ashford, KentPosts: 78
Hi all, this is the first year I have been lucky enough to have a greenhouse - well greenhouse/shed combo.

Currently I have some sweet pea seedlings that I am planning on overwintering in there, but the compost, although only watered once since planting, is still quite damp (There are drainage holes in there) so I am presuming its because it is cold. Is there anything that I can do to protect the seedlings? Its all very new to me overwintering things.

I also have penstemon cuttings I need to separate and don't want those going mouldy either...

Any help would be greatly appreciated!!

Dolce far niente....


  • FairygirlFairygirl west central ScotlandPosts: 47,179
    Sweet peas don't really need protecting, other than from heavy rain/snow etc. They shouldn't be cosseted   :)
    I don't grow penstemons, but they can be potted on when ready, and just kept ticking over. The growing medium is a big factor though - a good gritty mix, so that they stay drier is better if your conditions are damper.
    You'll find anything given a watering will tend to stay moist for ages, unless the greenhouse is in an area that catches sun enough through the next four or five months, and you're in a generally milder, warmer area. I rarely water anything over winter if it's in the greenhouse.  :)
    It's a place where beautiful isn't enough of a word....

  • LynLyn DevonPosts: 20,584
    Don’t worry about your penstemon cuttings going mouldy, most peoples do,  just leave them because in the Spring they start to shoot up from the base and you cut all that top growth off.   The new growth will be fine. 
    Gardening on the wild, windy west side of Dartmoor. 

  • Pete.8Pete.8 Billericay, EssexPosts: 9,079
    I overwintered sweet peas in my greenhouse once - they all rotted probably due to lack of airflow.
    Leaving them in an open cold frame somewhere sheltered has worked best.
    If you don't have a cold frame then just somewhere where they'll be protected from the the worst of the weather.
    As Fg says they're tough plants
    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • RedwingRedwing SussexPosts: 1,236
    Ventilation on all but the coldest days is important.  Of course, do not water unless there is a prolonged dry sunny spell and the soil dries out, which can happen in southern England.  Only a little in that case.

    Based in Sussex, I garden to encourage as many birds to my garden as possible.
Sign In or Register to comment.