Myth #1: You can only plant trees in the spring.
Spring is a popular planting season, but fall is equally great. The fall season offers ideal weather conditions for planting, with shorter days and cooler temperatures that help reduce transplant stress, so newly planted trees can easily adjust and thrive in their new home. Because soil often remains warm into the fall, following the hot summer months, it creates an ideal environment for new root growth immediately after planting.This helps young trees develop a strong root system as they head into the spring season. In addition, pests and diseases that flourish when the weather is warmer and cause stress to young trees, begin to decline in the fall.
Myth #2: It’s important to water your trees every day.
We may think daily watering is a simple gesture of care, but a tree can be overwatered just as easily as it can be underwatered. While water is essential for almost every aspect of tree growth, soils that are watered daily run the risk of becoming waterlogged. Waterlogged soils lack oxygen, which can suffocate roots, leading to symptoms such as wilting, leaf drop and even plant death.
On average, young trees should be watered twice per week from spring through fall, using approximately six gallons of water each time.This is the equivalent of using three full watering cans twice per week. When in doubt, check the soil under the mulch with your fingers – if it feels damp and cool, your tree should be good for another day, but if it feels hard and dry, your tree needs a drink!
Myth #3: Existing tree branches rise as the tree gets taller.
It is a common misconception that trees grow taller from the bottom up, just like grass; however, new growth on trees occurs in two distinct areas: the trunk and the tips of branches. Growth in the trunk allows trees to grow wider and growth from the tips of the branches allow trees to grow both taller and wider. This means that any branches currently on your tree will always remain at the same height and won’t move upward on the trunk as the tree grows (e.g., if a branch is located two meters above the ground, it will always remain at two meters above the ground).
While tree topping is a pruning practice that quickly reduces the height of a tree by removing all of the upper branches, it is a harmful long-term practice that increases tree stress and leads to structural risk.Topped trees undergo intense stress because most of their leaves (their food producing factories) are removed. To compensate for this sudden loss, trees produce many tall and structurally unsound shoots from their remaining branch stubs to photosynthesize. This reaction quickly increases the size of the tree, but this time, with weaker branches that are more likely to fail, posing a risk to both people and property – especially in urban areas.
When it comes to mature trees, good pruning practices state that no more than 25% of a tree’s crown (leaves) should be removed at one time. To minimize stress and reduce risk, always choose an ISA (International Society of Arboriculture) certified arborist to prune your tree.
Myth 5: Synthetic fertilizers are tree food that help boost growth in young trees.
When synthetic fertilizers are applied around or near a young tree, especially those high in nitrogen, it can cause rapid growth in the tree’s canopy, but not necessarily in the trunk. This creates an imbalance within the tree, wherein the canopy becomes very top-heavy, but the trunk is too small to support its weight. This imbalance can lead to the tree bending over or even snapping. Furthermore, synthetic fertilizers can also cause harm to trees by burning their roots- especially if applied incorrectly.
If you are looking to give your young tree a nutrient boost, apply a healthy layer of organic compost (about eight centimetres deep), such as sheep or cow manure underneath a layer of natural mulch in a doughnut shape around the trunk. Organic compost and mulch are natural fertilizers that slowly add nutrients back into the soil as they breakdown.
With these myths busted, are you ready to start planting? Learn more about our subsidized Backyard Tree Planting Program. We offer native trees and shrubs for residential homeowners, businesses and multi-units. For up-to-date, reliable tree care tips and guidelines, please visit our Tree Care page.
Jess Wilkin is the Residential Planting Programs Operations Supervisor and an ISA certified arborist at LEAF.
LEAF offers a subsidized Backyard Tree Planting Program for private property. The program is supported by the City of Toronto, the Regional Municipality of York, the City of Markham, the Town of Newmarket, the Regional Municipality of Durham, the Town of Ajax, the City of Oshawa, the City of Pickering, the Township of Scugog, the Town of Whitby, Canadian Trees For Life, Ontario Trillium Foundation and Ontario Power Generation.