Here is an ingenious idea that will give space for up to 24 more seed trays in an average 6'x8' greenhouse for the price of a few pieces of wood, that even a DIY novice can put together.
Here is what you need:
- Upright: 2 posts. 2"x2" is good but any old bit of wood will do as long as it will support the weight of your trays. The length needs to be the height of the roof edge of the greenhouse
- Centre Support: A flat piece of wood about 18" long
- Shelving: 4 pieces of 2x1, each piece being a few inches longer than half the length of your greenhouse
- a hand full of wood screws
- 8 nails
First of all you need to build the centre support, so screw the flat piece of wood onto the top of the two uprights, each should be approx. 12" apart. There, that's done, it should look something like this but it doesn't have to be exact.
Next you need to hammer 2 nails into one end of each the shelving pieces so they protrude out the other side. You want the nails as close to the end as possible, but again it doesn't have to be that accurate.
Take care of these nails sticking out.
Now you simply hook the nails over the cross bar on the end of the greenhouse and place on the centre support, two pieces either side and you're finished.
All done. You'll probably get 10-12 seed trays on each side of your greenhouse.
If you have existing staging in your greenhouse simply make the upright supports long enough to sit on the staging rather than going down to the floor.
And because this all stands up under it's own weight and there's no permanent fixing, later in May / June when all the plants are out in the garden you can simply take it all down and store away for next year, making space in your greenhouse for tomatoes and other summer crops.