By: Dave Zeldon and Ely Schweyer
Let’s get in depth about planting trees too deeply!
Sometimes homeowners find that their newly planted trees start showing signs of stress and become unthrifty a little while after planting, and soon their investment is altogether lost when the plant just dies. Often when we’re asked to inspect a tree in poor health, we know what to suspect.
Although not readily apparent at the time of installation, the long-term effects of improperly placing the root system in the planting hole are substantial. The poor tree health that results manifests itself as reduced growth rate, atypical leaf size and colour, and increased disease susceptibility. Trees in really poor condition exhibit decay, cracks, and excessive deadwood. Sometimes trees show signs of stress within the first year of planting, but it usually takes several years for the problem to rear its ugly head.
The most common reason? Many trees are simply buried too deeply causing the tree roots to decline in health, as they cannot get the vital oxygen from the air that they require to live.
Putting Down Roots
The width of the hole your tree will call home should be at least two times the diameter of the root ball, container, or in the case of bare root trees, the spread of the roots. This will provide the tree with enough worked earth for its root structure to establish itself.
For tree roots to grow vigorously, they require water, oxygen, and warmth. An oxygen level of 25% of the soil volume is considered good for root development.
At a 5% oxygen level, growth stops, and at 2%, roots decline and die.
Since tree roots naturally grow quite shallowly in the soil profile, buried root systems are unable to obtain adequate soil oxygen and water. As a survival response, trees work to get roots closer to the soil surface where there is a more reliable source of both. The energy that a newly transplanted tree should use to overcome normal transplant stress is instead used just to survive.
The tree expends its energy either by forcing its roots to grow upward or by creating totally new roots from dormant buds on the buried trunk, wasting all its prior growth. Some plants can survive being buried too deeply and live normal lives after developing a functional root system, others begin a long, slow decline of health resulting in either premature death or sudden failure during wind or ice storms. Let’s not risk it!
How Do I Know How Deep to Plant?
If you want your new tree to not only survive, but thrive, it needs the best start possible; it is very important that the root collar flare be visible after planting. The root collar is the part of a plant where the stem and root system meet, "flaring" where it transitions between the stem wood and the roots. Always make sure that the root collar flare is visible after planting. If settling occurs, reset the tree to the proper depth.
👉 Note: The backfilling soil should be a mixture of the original soil with composted manure or topsoil and bone meal.
But I Did Leave the Root Collar Visible… When I First Planted It
It has been observed that many times after a perfect tree planting, the homeowner then decides to build a raised-bed garden around the tree (thus burying the root collar flare – we’ve found root collar flares buried to 24 inches in mulch!) only to find that within a year or two, their young tree is dead or dying.
A common practice, often referred to as ‘volcano mulching,’ also contributes to this problem. In addition to subjecting trees to the problems associated with planting too deeply, heat from the composting mulch can literally cook a tree's trunk.
So, What is ‘Planting Proud’ Then?
The transplanting rules are amended if planting in the heavier clay soils where the practice of planting your new trees "proud" is advised. Planting proud essentially means that the root ball is left higher out of the ground level, producing a hilled effect. The soil that is normally used for back-filling is used to help to create a mound. Planting your trees this way in poorly draining clay soils prevents the ground water from collecting in an otherwise deep hole and drowning the roots of your new planting.
But, as a general rule, trees should be transplanted no deeper than the soil in which they were originally grown, and the soil level shouldn’t rise after planting. Two to three inches of wood chips is the optimum depth to mulch - and keep it an inch or two away from the trunk. If it is really desired to have the tree as a focal point in this newly built garden, then possibly a 3 foot well could be made around the tree to keep the root collar flare open to the air.
So, remember to give your tree a strong start and long life by not planting too deeply, but by leaving that root collar flare exposed! We hope these tips can help you encourage the longevity of your new tree. For more information - and trees - visit our Trees & Shrubs section at Eising Greenhouse and Garden Centre. We hope to see you soon!
Pruning is an essential part of gardening. Essential, but a little intimidating at first because it’s a broad subject. That said, there are some basic rules that apply to most trees and shrubs that will get you started.
There are a number of reasons to prune; the most obvious is for safety, to keep a branch from doing damage or harm by falling or rubbing against something like a building or another tree. Other important reasons include:
- Removing dead, diseased or damaged wood
- Shaping to make a plant bushier, reduce the size and bulk, or slow down growth
- Thinning to increase light penetration and airflow and reduce the possibility of disease
- Rejuvenation to encourage growth, blooming and fruit
Correctly pruning trees and shrubs can help with everything listed above and, most importantly, help maintain the health of your plants. Proper techniques and timing ensure the best results.
The Right Tools
You may need fewer tools to prune than you think!
Secateurs or hand pruners work well on smaller branches.
Loppers or lopping shears have longer handles for more leverage and are ideal for medium-sized branches.
A pruning saw works best for larger branches.
Electric or manual hedge shears are best for cutting a tidy wall of foliage like hedges and shaped evergreens.
The key with garden tools is to make sure they’re sharp and sterile. This can prevent the spread of disease. Clean tool blades with rubbing alcohol after trimming each branch.
When to Prune
Pruning timing requires some research as it depends on the species of the plant and the result you’re aiming to achieve. For example, some trees may be best pruned in the winter while they’re dormant and buds have not yet appeared. To shape a tree, it’s easier to prune before the leaves have formed so that all of the branches can clearly be seen. Pruning early in the gardening season will invigorate the tree. Conversely, pruning after the tree has formed leaves in June will tend to slow down growth.
When pruning flowering trees and bushes, there are other timing considerations. Some ornamentals bloom on branches that grew the previous year. Pruning those branches too early will result in fewer or no blooms. For these plants, it’s best to wait until after they have bloomed.
If you’re unsure about pruning timing for your tree or shrub, this is a fairly comprehensive list to use as a guide. We have also linked other resources below this article.
In general, late fall or early winter is not the time to prune any plant as it encourages new growth, which may be damaged by colder weather.
Pruning Techniques
While some trees may require specific care (pines, for example), here are the basic techniques for pruning trees and shrubs. It’s a good idea to know these basics before you head out to begin cutting branches.
Examine the branch, buds and shoots before cutting. Cutting above a bud facing away from the trunk of the tree will have the branch continue to grow in that direction.
Cut on a 45° angle just above a bud whenever possible. Keep your cut above the lowest bud (the bud closest to the trunk), or the branch will die back.
Before removing a large branch, cut ⅔ off the end of the length to reduce the weight. Once the bulk of the branch has been removed, then cut the rest of the branch away from the trunk by cutting close to, but not into, the “collar” of the branch where it meets the trunk of the tree.
Now You’re Ready to Begin Cutting!
Now that you know the techniques for pruning, where do you begin? Here’s a logical set of steps to follow:
1 - Remove any dead or diseased wood
2 - Remove any branches that are crossing and rubbing together. For a shrub that’s too crowded, remove the thickest branches down to the ground first
3 - Remove water sprouts
4 - Stand back and observe the shape of the tree. If anything is not pleasing about the look (lopsided growth or branches growing too close together or at a sharp angle to the trunk, for example), begin removing or trimming back one unsightly branch at a time. Observing the shape between each cut
5 - Remove any suckers or stubs
Follow The ⅓ Rule!
Once you start, pruning can be fun, but be careful not to get too carried away. Trim up to ⅓ off of an established plant (not a newly transplanted tree or shrub) in one growing season - maximum. Cutting off too much can stress the plant and impact its overall health.
Lastly, know that you can always hire a certified arborist if the task is too much or the tree is simply too large!
Other Resources:
- City of Moose Jaw: Pruning Trees
- Landscape Ontario: Pruning Shrubs and Evergreens
- Ontario Government: Pruning Fruit Trees
- University of Georgia: Pruning Ornamental Plants
