Topic: Age old question - To slab a GH or not ?

[Pesky Wabbit]

I'm sure this has been asked sooooo many times before, but nothing comes up in a search...

I've just put up a 6*8 GH. What are the advantages/ dis of :-

       a) slabbing the whole of the floor so that its sealed against anything coming through;
       b) just leaving the bare soil and planting straight into that;
       c) having a slab path down the middle.
 
particularly with regard to watering, pests, fertilizer and having tall(er) tomato/cucumber plants.

[kt.]

Ooh, ooh, pick me pick me. I know this one...

I laid a concrete base in my greenhouse 3 years ago. The plants can dry out quick in the warmer weather. Irregular watering also affects the crops. Last winter I removed all the glass to move the greenhouse. Then smashed up and removed the base. I now have a centre path from the door, with a 'horseshoe' shape of digging ground around 3 sides. Last year put this to the test. The crops needed less watering, grew taller, had less disease and fruited  more harvest. Yes you have to whip round with a hoe occasionally and it may not 'look as tidy' as one with a base, but the yield and quality of crop far outweigh this.

[fuzzycuzzy]

 That sounds good advice.I would slab a central path too.Thats the plan for my recently bought 12'x8' GH but my only concern is the wretched clay soil underneath the site onto which the GH is based.Thought about raised beds or just to be patient and dig in plenty of good stuff over the next few years. Any suggestions?

[Pesky Wabbit]

One of my concerns with just having a central path was the depletion of nutrition and the build up of P&D.

Would I have to completely dig out and replace about a foot of soil every few years ?

[RobinOfTheHood]

Ooh, ooh, pick me pick me. I know this one...

I laid a concrete base in my greenhouse 3 years ago. The plants can dry out quick in the warmer weather. Irregular watering also affects the crops. Last winter I removed all the glass to move the greenhouse. Then smashed up and removed the base. I now have a centre path from the door, with a 'horseshoe' shape of digging ground around 3 sides. Last year put this to the test. The crops needed less watering, grew taller, had less disease and fruited  more harvest. Yes you have to whip round with a hoe occasionally and it may not 'look as tidy' as one with a base, but the yield and quality of crop far outweigh this.

Totally agree, I have one with a base and one with a central pathway, exactly as KT said re watering and growth. Also no diseases as yet, touch wood, apart from blight on the toms, with which the based gh fared better, presumably because it's drier.

I have cleared probably 9" of soil out each year, though, and dug in manure.

Certainly a solid base would require more attention re watering, not too bad if you can spend a lot of time there.

[kt.]

One of my concerns with just having a central path was the depletion of nutrition and the build up of P&D.

Would I have to completely dig out and replace about a foot of soil every few years ?

No effect on nutrition as long as you fed the soil when not in use so it can re0generate. Makes no difference having a path. If you dont want to lay slabs on plastic, put 2 scaffolding boards side by side, secured together with a short  wooden baton. Not forgetting a plastic membrane underneath.

[grawrc]

For me the problem with the gh soil is that I tend to grow the same things every year (mostly tomatoes) so I dig out and replace a fair depth of soil every 2-3 years to stop soil problems developing. If I don't have time I stick them in growbags on top of the soil.

[davee52uk]

I have two small greenhouses on the lottie. Both have bricks down the centre for a path and beds both sides and at the end which is original soil. I've added loads of manure into teh beds as well.

Disdavantgaes are that you get loads of weeds such as couch grass coming through and you eventually will have to change the soil - probabaly after three years.

On the other hand it doesn't need a lot of watering, especially when it rains outside.

[Pesky Wabbit]

Thanks to everyone.
Its clear to me what I now need to do.


Pesky.

[Two Choices]

Hi Pesky wabbit, I went through the same dilema and ended up covering the floor with 3 inches of pea shingle. I then grow in large pots and containers. I find it suits me as the weeds are easy to lift, the plants are always in fresh soil / compost (which gets recycled over the beds the following spring) and the pots drain away freely. Good luck. TC

[Jitterbug]

I also have a centre path for paving stone both on the allotment and at home in the smaller greenhouse and the results have been good. 

If you needed to sterilise the soil you could sow Caliente Mustard into greenhouse beds in Mid October and cut down in the Spring and rotovate the soil and cover with black polythene for two weeks. But as mentioned above just feeding and replenishing the soil should be enough.

Jitterbug

[Columbus]

Hi Wabbit, Hi all,  :)

I got a green house last year. it stands on huge railway sleepers but has an earth base inside.
During the autumn, rats and mice have tunnelled under the sleepers and rats have been seen sunning themselves on my staging. How they know that its worth the effort of tunneling I cannot imagine.

I have layed traps and killed the visitors. I have mesh to sink around the edges outside to make tunneling more difficult and cleared the area around the back of the greenhouse where they were getting in. I`d like to chit my spuds in there but don`t want to encourage them back in.

You might want to consider entry by rats when making a base for your greenhouse or any allotment building.

Col