New greenhouse / how to make a base

Hi there, I'm completely new to the forum and have only be growing veg for a few years mostly in pots. I only grow stuff I can eat.....not so interested in flowers (leave that to the wife / mother-in-law)!

I've purchased a small greenhouse - a gardman 6'x4' - I wanted perspex as we are working on having kids and glass would probably be a nightmare. Whilst I would have liked a bigger one that's the size that'll fit well in the part of the garden I want to use.

Greenhouse will be for growing veg stuff, mostly in either pots or growbags. Plan to grow tomatoes, chillis, peppers, strawberries, mange tout (outside the greenhouse), courgettes (outside) lettuce and pak choi.

My query is around the base - I've bought the frame plus an optional metal base. So say this can be put straight onto relatively flat ground and ground anchored in. To me that sounds a bit lightweight, and we have fields behind the house, so want it firmly anchored down, and not able to twist, so hopefully the polycarb won't fall out in high winds (it's twin wall).

My thoughts are to dig a perimeter trench in a rectangle shape, then use some kind of gravel / hardcore in the bottom of it to level it out (ish). I'm then thinking about putting in concrete blocks (the grey building ones) on their sides, so 2/3 of each block is underground, and 1/3 is above ground. I'll then bolt the metal base to this, then the greenhouse to the base. This will also give me a little more height in the greenhouse as it isn't the tallest thing in the world.

Does this sound reasonable / are there any other suggestions?

After that I need to suss out what I'll use as the floor in the greenhouse - at the moment the area is mostly hardpacked lawn. Wondering whether to use weed barrier, or black plastic sheeting to go over the grass - then gravel most of the area, just with a few slabs as a path down the middle.

My one question then would be around drainage - I guess I could drill a large hole through one of the blocks level will the floor and put a pipe through it (I have an sds drill) into a soakaway in front of the greenhouse. Do I need to bother, or is it likely to be ok if I just put a few holes in the black plastic sheeting under the gravel?

Any comments / suggestions are much appreciated as I'm just making this up as I go along in some respects. I'm reasonably good at DIY so happy to consider most things!

 

We dug out the whole base to a dept of around 8" and levelled it with hardcore. We then put a path of slabs in the greenhouse and finished it all off (I have a hard standing area in front of my greenhouse) with weed suppressing membrane and Cotswold stone on top. It is edged with curved edging stones on the side and front to look nice.

 

Welcome to Gardeners Corner Joe.

If you don't intend to use the ground inside the greenhouse for planting I wouldn't bother laying blocks and putting gravel down. Why not just make a concrete base, you can raise the level to bring the height of the greenhouse up and also bolt it directly to the concrete. This is what I have done as I live in a windy place and during the winter months my greenhouse has to cope with gale force winds regularly.

Living in a windy area is not ideal for Perspex, the wind is likely to suck it out. I opted for toughened glass, it will cost more and it's heavier but won't break like horticultural glass, it shatters like a car windscreen into tiny pieces. This would be safer for your future children. My young grandchildren play around mine with a ball and I have no qualms about their safety.

 

perspex makes some racket too in the wind, it was only a matter of time before one of the neighbours complained about our one (it was like someone with a set of drums at times) we had nowhere else in the garden to move it so it had to go im afraid

 

Thanks for all the replies.

I wouldn't say where we live is massively windy, so hoping Perspex is ok. Just there is a playing field behind the house, although it's blocked out with 6' high fencing. The greenhouse will have a fence about a foot behind it and the house should protect it from wind on 2 sides.

In terms of direction the ridge should be going approx East /west and it'll get full sun from the south. A little worried it might get very hot from comments - it doesn't have a roof vent, just a 5 louvre vent on the back wall with an automatic opener. Guessing I might need to leave the door open on hot days in the summer.

On growing in the soil I've not had much luck at this house. The soil is heavy and has clay in it. I tried growing beans / mange tout in it last year and it was rubbish compared to the stuff I grew in pots. I'd dug in a lot of compost prior to planting and used plant feed but to no avail. However, courgette plants grew in it no problem.

I had toms in pots last year in one of those 4 shelf mini greenhouses with a plastic zip up cover on and they did pretty well. Grew them from seeds but they were very late harvesting - I was still picking cherry toms from them into November.

Not sure what to do with the base yet then. Think I'll price up concrete blocks and gravel vs an entire concrete base and see what that looks like.

Hoping the greenhouse allows me to grow peppers and chillies this year - failed miserably the last 3 years on those. Got a heated propagated this year so just planted seeds in it this week which I'm keeping in the conservatory. Hope this gives me a good head start.

 

Thanks jwk, all comments gladly received.

I'm a beginner in the garden (only had my own house with a garden for a short while), but think I'm ok at researching things online and considering how I'll do something!

 

If it gets to hot in your greenhouse you can always white out the roof glass/perspex to help keep the sun off.

Keep us posted on your progress please Joe.

 

Hi,

I am new here and new to gardening, I have just built my base today, I still have more work to do and I was also lucky the best place for the greenhouse was up to two supports.

 

That looks comfortably bigger then the one I've bought. How are you going to fill the gaps where the frame is level but the ground goes away?

I'm going to start looking at foundations for mine next weekend. Used my chainsaw for the first time today to take down a tree that would have over hung where the greenhouse is going.

 

Hi Joe, I did this with it today.

 

Looks good what you have done so far, would the base have been
better a bit further away from that wall (look like a garage), just
in case you have to do maintenance to the windows?

 

Hi intel, the glass will be fitted just over the green window from the inside of the greenhouse, the only need for glass here is to let light in to the shed. the front entrance is south facing.

 

I see, guess that's a neat way to cover the gaps!

So is that a wooden frame under the greenhouse and how deep are the struts going down into the ground / are they set in concrete?