Six keys to planting trees: Mark Cullen | Toronto Star

It was while hiking in Killarney Provincial Park, at the north end of Georgian Bay, with my son, Ben, this summer that it hit me: all my attempts to plant trees can’t compete with Mother Nature. There she was, growing birch and cedars out of sheer rock at an 80-degree angle. How on earth did she manage to get her trees to grow without earth when we mortals have our problems when planting in rich soil? A lifetime of tree-planting and tree-hugging has taught me a thing or two about them. Sept. 27 is National Tree Day in Canada — the perfect time to create a living legacy in your own yard. Here’s how to ensure the best chances for tree-planting success:

When shopping for a tree, look for a young, vigorous specimen. The keyword here is “vigorous,” as in ready to go. Young trees have young roots that are in the pot. When you buy a large tree, usually wrapped in burlap and placed in a wire basket, many of the young, fibrous feeding roots are still in the ground on the nursery farm. Young trees want to put down roots and get growing. They usually catch up and surpass the growth of a larger tree within a few years. Here in Southern Ontario, our soil is limestone-based and alkaline. There are some sandy spots near the lake, but most of us have to deal with clay-based loam or solid clay — and it does not drain efficiently.

I plant all of the trees about 50 to 70 centimetres above grade and mound quality soil up to the “flare” of the tree. The root flare is where the main trunk of a tree meets the roots. If you cover up the trunk with soil, you risk smothering it and likely causing a slow death. Don’t bury the trunk.

I mentioned quality soil: well-drained, nutrient-rich, organic — and lots of it. I use a combination of 70 per cent well-composted cattle manure/mushroom compost and 30 per cent sharp sand. Composted manure provides all the nutrients needed to support tree-life. No need for chemical fertilizers. The sand provides drainage, as very few trees enjoy having wet feet. Sharp sand is sometimes called Builders’ or Play sand, as in the stuff that you put in a sandbox. But it is not beach sand, which is too fine for water to flow through freely. A reminder: use lots of new soil. For a two-metre-high maple tree, you should use four to six bags of quality triple mix or garden soil.

It will take up to five years for your new tree to put down roots and anchor itself into its new home. A tree stake on the north or west side will help to hold it upright in stiff winds until the day comes when it can support itself.

Think about the location of your new tree and consider the space that it will eventually take up. Twenty or 30 years seems like a long time away and you may not even care what your tree will look like at that time. But you will be amazed at how quickly a tree can fill in the space that you allow for it, even a small tree such as an ivory silk lilac. There is a golf course near my home that was established a little more than 50 years ago. The founders invested in hundreds of fast-growing poplars, willows and soft maples when they designed the course. No doubt they wanted the shade and tree cover in a hurry. Trouble is, they are cutting those trees down now and the course is looking rather bare. Had the first members of the club planted quality sugar maples, lindens, oaks, beech and other hardwood trees, they would be enjoying an amazing canopy of shade that would last for up to 300 years. We plant trees not for ourselves but for our grandchildren and for theirs, as well. It is an unselfish act that pays untold dividends down the road in the form of oxygen, a cooler environment, slower street traffic, enhanced real estate values and an altogether nicer place to live, work and play. If you can’t plant a tree on your own property, consider having one planted on the Highway of Heroes by donating. We are planting 117,000 on the Hwy. 401 right of way, one for each of Canada’s war dead since Confederation. Details at hohtribute.ca. For more columns by Mark Cullen, visit thestar.com Mark Cullen is an expert gardener, Order of Canada recipient, author and broadcaster. Get his free monthly newsletter at markcullen.com. Look for his new bestseller, The New Canadian Garden, published by Dundurn Press. Follow him on Twitter @MarkCullen4 and Facebook.