We humans get most of our nutrition from seeds, and so do many other mammals. Squirrels and mice are all
expert at smelling out nut tree seeds. Once the seeds germinate, mice switch to nut seedling salad, and are
joined by groundhogs, rabbits and deer. One useful and inexpensive defense against all of these is the ECSONG Grow-Box.
To build one you need:
four 2x2 (1½" square) wood posts, 3' long
one sheet 3/8" exterior chipboard (4'x8') - sometimes called Aspenite®
four pieces 1x3 (2½" wide) x4' strapping (cheap spruce)
two small gate hasps
4'x4' chickenwire or hardware cloth, ½" mesh
Cut the chipboard in half lengthwise and crosswise, making four pieces 2'x4'. Nail the 2'-wide edges to the
posts so that all four posts stick out the same side. Prepare a 4'x4' seed bed, dig a slot 6" deep all
around, and a hole 18" deep at each corner. Your box assembly will now drop into place with the chipboard
sides in the slot so they reach 6" below the earth surface. Backfill the slot and holes.
Cut 5" off two pieces of the strapping, making them 3'7". Lay the four pieces flat and square on the floor
with the short pieces inside the long ones, then staple the wire mesh onto them. Fasten a hasp to the
middle of two opposite sides, and the matching loop to matching sides of the box so the hasp holds the
cover on the box firmly when held with a stick through the loop. Your box is now ready for planting.
1/4" chipboard is cheaper, but tends to collapse under snow load over winter - 3/8" is better for Ottawa.
Don't use particle board (made from sawdust) - it won't stand up to rain or snow. Plywood is quite a bit
more expensive than chipboard and doesn't last any better in contact with soil.
The cover will hold together better if gussets (triangular pieces of chipboard or plywood about 5" to a
side) are nailed over the mesh into the strapping at the corners. I no longer recommend the polyurethane
glue shown in the photos, it fails after 2-3 seasons outdoors.
The box will hold together better with screws than with nails - 1½" no.8 round head are good.
The box can be made any proportions that add up to 8' with no waste of material. A 3'x5' box is shown in
the photos - easier to reach in the middle for weeding than 4'x4'.
Hardware cloth (welded wire) is more expensive than chicken wire, but much more durable - Ottawa snow
load stretches chicken wire down a lot over winter. But, some nut trees, black walnut in particular, grow
through the mesh their second year - it's easier to just cut chickenwire away from around them and patch
the wire than it is to tease them back through hardware cloth without damage. Voles get through standard
1" mesh chickenwire - ½" mesh or smaller is required.
If you go to the expense of hardware cloth, it's worth using stainless steel staples.
If it's in public view, green deck stain (solid hide latex) lasts better than paint on wet wood.
One option for tall growing seedlings is a height extension on the cover as shown in the last photo. It
doesn't stand up to snow load in Ottawa winters, but will protect the seedlings during a third summer of
growth. The extended cover should be removed before the third winter and standard tree protection added
Making the sides of wire mesh lets more light in, but also more weed seeds. The solid sides encourage
seedlings to put on height, which is desireable.
a complete grow box
a cover height extension