TALL AND STATELY
Shade Trees — Our Beloved Summer Saviors
By Linda B. Gay, Horticulturist and Gardener | Photos by Linda B. Gay
Selecting a tree for your home or workspace is like buying a pair of shoes; you want to make sure it fits and has the desired shape. Other factors include leaf type, fall color and whether or not you want flowers.
Trees are grouped into small, medium and large categories and knowing the mature height and spread when it’s fully-grown are critical to making the best selection. Note that a tree’s feeder roots always extend at least ten feet past the drip line of the tree, the furthest tips of the tree branches, so use this information to determine the best variety for your spot.
When creating a tree-planting plan it is much better to plant five-, ten-, or 15-gallon trees because with proper care the roots will become established in two seasons. Smaller, younger trees are like small children; they have lots of juvenile hormones and are more vigorous than trees grown in 30-, 45- or 65-gallon containers. Larger, older trees do not establish quickly and can take several years to root-in, turning the homeowner into a nursemaid hand-watering the trees until they become established. Smaller trees are easier to handle, more economical and respond faster to the environment.
In selecting your trees from the nursery make sure they are healthy, strong and straight. Inspect the trunks and branches to ensure there are no cankers on the bark or the trunk — similar to the ones we get in the mouth — as these are an indication of a sick tree. Also inspect the trunk for unnatural cracks or loosened bark. Without bark there will be no flow of water and nutrients to the top of the tree; that side of the tree won’t be able to thrive and will eventually die.
Reasons to Plant Trees
There are many reasons for planting trees. For shade in the summer but sun in the winter, select a deciduous tree that will lose its leaves during the wintertime: Shumard Red Oak and black gum are excellent choices. Houston is one of the 16 cloudiest cities during the winter months and we want to enjoy the sun when it chooses to come out. Planting for summer shade normally will be in the western exposure, but morning sun in the east can be just as brutal.
Trees also work well as privacy screens; the best choice here would be a group of trees that are evergreen and grow more slowly than deciduous trees. Another good choice would be a large evergreen shrub that provides ten- to 15-feet of height for privacy and where the shrubs are branched to the ground. It’s important to note that shrubs are faster growers than evergreen trees. For shady spots select viburnum Awabuki or Japanese yew; for sunny areas choose pineapple guava or olive tree.
When deciding on a flowering tree, first determine whether it’s a sunny spot (receives six or more hours of direct sunlight) or a shady spot (fewer than six hours of sun). For shade select a Japanese magnolia and for sun choose a Chinese fringe tree.
The Dos and Don’ts of Planting
There are so many ways that a tree planting can go wrong. From the difficulty of Houston’s clay soil to placement, mulch types and pruning, this is an area where even those with the greenest of thumbs can get in trouble. Refer to our handy ten-step guide on page 74 for best practices.
The Tree is Planted. Now What?
Do not depend on irrigation systems to water in a newly planted tree. Hand watering with a hose at least three to four times a week will help your fertilizer, soil, and shale “marry” to create the perfect growing environment for your new tree.
So come out to The Arbor Gate and let us help you select just the right tree for your landscape.
Ten-Step Guide to Tree Planting
1. Dig your hole twice as wide and twice as deep as the root ball. Remove the soil from the hole and put it into a wheelbarrow or tub to make mixing easier.
2. Chop up the clay in the bottom of the hole and add one third of a 40-pound bag of expanded shale and one pound (about the size of a coffee can) of Arbor Gate blend, then mix with native soil and shale.
3. The soil in the wheelbarrow should be chopped up and blended with more shale and another pound of organic fertilizer.
4. If the root ball is pot bound, meaning the soil is not evident in the root ball, then cut or score the roots. Cut one to two inches off the bottom (similar to the shape of a Frisbee) and slice the sides of the root ball into quarters from the top of the root ball to the bottom with a serrated knife or pruning saw. If the root ball is not pot bound, don’t prune at all. Pruning a pot bound root system stimulates new roots that will actively start growing once placed into the ground. I also like to prune the top edge of the root ball (a bevel-like rounding), to reduce the possibility of the root ball drying out when exposed to the air, since we plant trees two- to four-inches higher than the existing grade.
5. For proper placement, lay your shovel across the hole to determine how high to raise the root ball. You want the space where the trunk and the soil meet to be above the shovel handle. Backfill around the root ball with the blended soil and gently tuck in. When backfilling the mixed soil, do not pack the soil as this pushes out the air spaces and reduces water percolation of soil. Gently tuck the soil around the root ball and build up the reservoir/berm at the edge of the tree well.
6. Dig out and remove any grass from around the tree: at least four feet across for a five-gallon tree and six to eight feet across for a ten- to 15-gallon tree. Mulch with pine needles or pine bark mulch.
7. Never mulch with dyed red mulch (made from hardwood pallets or pressure treated CCA lumber) or black mulch (ash is added to color it black and make it look like humus). These mulches are like fast food: no nutrition, just death and disease.
8. Create a four- to six-inch wide berm (mound) of soil just inside the grass ring to hold water and nutrients when you hand water the tree. This also acts as a reservoir when it rains; the rainwater will be captured and directed to the root zone. It also keeps weed eaters away from the trunk. This planting will have a concave (inverted) reservoir — the opposite of a volcano shape.
9. Do not remove the lower branches of evergreen magnolias; the wound never heals and will leave it susceptible to rot, bacteria and insects. Healthy trees can have their branches all the way to the ground.
10. Even in wet areas it is advisable to work expanded shale deep into the soil to create air pockets so that the roots will be able to grow and breathe.
The Arbor Gate, 281-351-8851, 15635 FM 2920, Tomball