One set of trees is planted near the front, and trained to an arched trellis b.
At Leitmeritz there is an iron trellis bridge, 600 yds long.
In any case the front trellis should stop conveniently short of the top of the sashes if there are trees against the back wall, in order to admit light to them.
It must be remembered that nails spoil a wall sooner or later, whereas a wire trellis is not only much neater, but enables the gardener to tie his trees up much more quickly.
Very durable trellises for greenhouse climbers are made of slender round iron rods for standards, having a series of hooks on the inner edge, into which rings of similar metal are dropped; the rings may be graduated so as to form a broad open top, or may be all of the same size, when the trellis will assume the cylindrical form.
