The Leyland cypress (Cupressocyparis leylandii) results from crossing the Monterey cypress with the Alaskan cedar. Its discoverer and namesake, C.J. Leyland, found six of the seedlings in the south of Wales in 1888. The cypress grows very fast to as high as 40 feet and as wide as 30 feet. The trees are popular as windbreaks and hedges, and many people use them for Christmas trees.
Planting the Tree
Dig a hole for your Leyland cypress that’s about a foot deeper and wider than the root ball of the tree. If the soil is sandy, mix in enough compost to help it hold water. If the soil is clay, combine it with potting soil to give the roots of the young tree something easy to penetrate.
Pull up and throw away any weeds from the soil you’ve spaded up.
Put the tree into the hole and push enough dirt under it to bring the top of the root ball up to about two inches below ground level. Push soil under, around and on top of the root ball until you've filled the hole.
Protecting the Tree
When you’ve settled the tree firmly in its new home, measure the tree across its center, from the tips of the outermost branches on one side to the tips of those on the other side.
Using that measurement as a guide, cut a piece of plastic ground cover big enough to cover the entire area under the tree. Trim the edges of the plastic so that the ground cover is circular.
Fold the circle in half, in half again, and in half a third time. At its center, cut out a hole that’s large enough to accommodate the trunk of the tree. Unfold the plastic and split it on one side only from the hole in the center out to the outer edge.
Open up the ground cover and slide it around the tree, with the hole in the center around the trunk. Spread the ground cover out flat beneath the tree. Overlap the open sides so that no weeds can grow up through the split in the circle.
Cover the ground cover plastic with a thick layer of bark mulch, straw or hay to keep weeds out.
Water your new tree well.
For routine watering thereafter, a drip irrigation system will give you the best results. If the tree doesn’t get adequate water, its growth will slow, but underwatering is better than overwatering, since the latter can cause the tree’s roots to rot.
Fertilize your Leyland cypress with a water-soluble, time-release fertilizer, liquid manure or fish emulsion.