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Green Houses

I'm moving house very soon (bubblewrap is my friend) and I have been gifted an old green house which just needs a few panels of glass replacing. I've only ever had a wee plastic pop up tent type thing from Aldi before so its going to be interesting having this additional space to play with.

There's already one in the garden that is staying which is (I think) laid on a concrete base so this second one is going to be tucked up behind it. The ground is going to need preperation which has gotten me thinking. Is there an ideal base for a conservatory? For instance would it be better to have a concrete or brick base for the frame but gravel directly on soil beneath for the actual "working area" to allow water to drain away? Or does this just cause no end of problems? Alternatively I'm thinking about laying a concrete base throughot and then building the green house up several inches on bricks to give me a little more height. Would drainage "holes" or using vent bricks be an advantage?

Since I'm starting off fresh and empty what do you suggest for storage / worktops? Are there materials you'd recommend or suggest I avoid? Is it best to use shelves that are grated to allow a good air flow?

Once we've unpacked the pots and delicates I'm going to try to reuse the bubble wrap to insulate at least one greenhouse. Do you need to insulate every sheet of glass?

What are your suggestions? (And if you have any advice on errecting a green house and hints and tips on greenhouses in general I'd be very grateful!!)



  • Birdy13Birdy13 Posts: 595

    Hi Clarington:

    When you said "Is there an ideal base for a conservatory?" I take it you still meant "greenhouse".

    (The modern meaning of conservatory - a "living room" room built out into the garden would definitely imply the need for proper concrete base and footings for a low level wall.)

    I'll assume you were still referring to installing your 2nd greenhouse.

    II assembled my own lightweight 8' x 6'  greenhouse (green aluminium frame with polycarbonate sheet windows) directly onto well levelled, well compacted soil which I covered with good quality black membrane and shingle on top of that. A narrow central path of slabs running from the door to the back makes it comfortable to stand on.


    Of the other two options,

    1. I would not want a full concrete base (no drainage for your plant watering)
    2. Bare earth is fine if you actually want to plant I to the ground - I would still want a central aisle to stand on though as quite a lot of watering could be needed inside for your planting as it will get none from outside and what it does get will soak into all the soil, some of which you will have to stand on.
    3. The advantage of my arrangement (photos) is that pots can stand on the shingle which drains easily after watering. The disadvantage is the membrane and shingle stops you from planting directly into the ground.

    Virtually no weeds have made there way through the membrane in the 15 years it's been up - just a bit of chickweed which is easy to pull up.

    The only bits of concrete were a large block at each corner and (if I remember correctly) half way along each of the long sides, to imbed the corner anchorages for the frame while the concrete was wet.

    Positioning for these anchorages, however, has to be exactly measured and the frame (seen as grey in this photo) must be completely square and completely level for the greenhouse to fit together properly. I know that sounds worrying but it just takes a bit of careful measuring and checking for levels.


     Hope the above helps.


  • Hello there,

    The bubblewrap needs to be as big a bubble as possible to let as much light through as possible.

    Some things I have learnt the hard way:

    • When putting your glass in, do the roof first.  This helps to square up the walls. Use new clips and greenhouse adhesive foam tape.
    • If you are taking the green one down you will probably find that you shear a lot of the bots that hold it together (50% of mine did).  They are very cheap to replace.  If you can afford it, I would replace all of them.
    • If one of the panes breaks in your greenhouse and you can't fix it right away remove a pane from the opposite side.  This will prevent it behaving like a parachute when the wind blows and there is less chance your greenhouse will get damaged or even blown into next door's garden (one couple on our allotment found their 8'x6' greenhouse 50 feet away after a storm during the night).
    • If you want to grow grapes in one then you'll need a hole in the wall to train the vine through - you plant the vine outside and train it into the greenhouse (only the fruits need the heat) as the roots need plenty of moisture.

    I don't think you'll have a problem with wanting water to "drain away".  In the summer I daily add a can of water to the floor of mine to try to increase the humidity and my base is patio slabs laid directly on earth.

    Good luck


  • Birdy13Birdy13 Posts: 595

    The concrete blocks are, of course, underground, holes filled with concrete around  carefully positioned anchorages - seen as the verticals in my last picture, screwed to the frame.

    Sorry, I forgot you mentioned you had glass not polycarbonate. That will be heavier and may need a low brick base - not an expert on that I'm afraid.

  • Mine is glass and is fixed to sleepers that were dug into the earth - we're not allowed concrete or mortared walls on our allotment.  It was a bit of a back breaking exercise as they have to be perfectly level (I roped in some help).  I would say that the base took longer than the rest of it put together.

  • Birdy13Birdy13 Posts: 595

    Ah, yes, of course! Sleepers! What would gardeners done if railways hadn't been invented?

    And interestingly, they are a perfect size (about 8 foot long, I think) not just for greenhouses but also raised beds.

  • DiddydoitDiddydoit Posts: 801
    I am having trouble with mine already as a kind of fungal disease is already present like last year it just seems to cover the plant and when toughed it just f,alls to dust as so to speak.So i will now be opening my greenhouse as much as i can in the day time and just provide heat at night time when frost is present. another factor may be that the small greenhouse is packed to the gunnels with plants as OH wont have them in the house.
  • fidgetbonesfidgetbones Posts: 17,235

    What plants have you got with this fungal disease, diddy?

    I've just sack barrowed 2 big agaves in to the greenhouse. As the pots are still soaking wet, I cant lift them up on to the bench, I will wait for them to dry out a bit. I keep them quite dry over winter. I have electric fan heater so air circulates quite well. When I had a paraffin heater in the old greenhouse, the condensation was terrible, and encouraged funal disease.

     I pick up as many of the old vine leaves as possible, and try and keep it clean.

  • ClaringtonClarington Posts: 4,949

    Thanks ever so much to everyone your replies they are quite invaluable and so much more informative than blindly looking at websites! I hadn't even thought about growing a grapes in a greenhouse, I will go forth research it and bare it in mind when replacing the broken panels.

    I definately meant green house not conservatory! Not sure what my brain was thinking there the house doesn't even have a conservatory.... yet.

    The car windscreen informed me of our first frost of the season today. Looks like I will need to get more bubble wrap to protect a few delicate pots. The local DIY store must be wondering what the devil I'm doing with it all!

  • ginagibbsginagibbs Posts: 756

    Hi Clarington, re bubblewrap. I would insulate all the panes if you are in a cool area. It might also be a good investment to get a parafin heater or electric for really bad weather.


  • Although parafin does produce a lot of condensation

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