I've recently received some questions via emails and in person about the Wicking Worm Beds beds.
Will the beds become waterlogged in heavy rain?
Remember this diagram from this link on The Basics of Wicking Beds (click it to see it better)
In the left hand, bottom corner is a tag called "Gap for Overflow".
If the wicking beds are built with an adequate drain hole (Gap for Overflow) above the bottom "pool" area they should not fill above that level. The excess will "leak" away.
As the growing area is raised there should be no chance of flooding, it will drain naturally.
Make sure the "soil" you fill the bed with has lots of compost in it. The plants will use the water as in "normal" beds, these raised beds will have better drainage that "normal" ground level beds.
In my "in ground" beds this drain point is at ground level (but doesn't have to be) and I can see the water escaping from that point so I know when the beds are full. This is also where any excess rain will escape.
If this point is lower in the ground the theory is that excess water will drain into the surrounding soil. That is providing the surrounding ground is not already saturated.
The only time I have noticed a problem was in some of the older Wicking Boxes.
The holes in the side had become blocked and were not draining. During a reasonable downpour the worms were escaping everywhere! I fixed this by putting a short piece of poly hose in the hole to drain them.
These older boxes were made with vegetative matter in the base, this has now collapsed as it has broken down and this seems to have caused the blockage.
The new boxes I've made this year have a 15cm piece of 13mm poly hose inserted through the hole in the side. They seem to be draining successfully now.
I'm also using a mixture of small gravel and sand in the bottoms of the boxes and 'stacking' some gravel around the outlet holes for drainage and to help prevent them clogging.
While it is raining regularly, even a little, you should find less need to water (filling the bottom pool area should not take long at all). One of the best things about these beds is that they make full use of any rain that falls on them.
I have only this week needed watered the beds since May.
Another question was about the size of the beds.
Basically you want them wide enough to be comfortable for reaching into the middle. You can not walk on these beds. Apart from squashing the worms you will compact the soil and reverse all of the good work they do aerating the soil.
The length of the beds would depend on how level your site is. The bases of these beds must be perfectly level for the wicking process to be uniform throughout the bed.
If the water pools at one end that is lower, that end will be wet but the other areas will dry out too much. It would be better to build smaller beds and 'terrace' them down the slope.
I did not remove the curtain covers from the beds this winter. This seems to have given the plants shelter from the cold as growth in these covered beds has been more successful than in others I have left uncovered.
It really is important to start growing winter vegetables during summer though. Most of the seeds for these crops were sown in early January. They need to be well grown before May when our cold weather sets in and growth slows down.