Our newly erected greenhouse is flooding during the recent heavy and prolonged rains.Not coming in from above, but seeping up from soil.My husband dug out the base earth, layed a layer of 20mm gravel and filled in with good topsoil, but today we find it is flooded again. Greenhouse is mounted on sleepers, with soil inside and slabs making a pathway up the middle. What can we do. I haven’t started growing anything in the greenhouse as yet.
If you can raise the level of the soil in the greenhouse higher than the surrounding ground, this will help but there will still be a high water table, with risign water, and this is not ideal.
It might be possible to dig a large soakaway, perhaps as much as one metre cube and fill with stone to within 30 cm of the top… the idea being to drain the water down into the soakpit from where it dissipates.
There is quite a bit of work in this and it might be as easy to move the whole greenhouse to higher ground if this is possible.