Planting Trees at a Park or Street Tree Event

A tree planting day is judged two summers later, when the trees either stand in leaf or stand as dead sticks in a line of stakes. The one idea that matters most is that the planting day is the easy part, and the sizes, the spacing and the aftercare plan decided before it are what keep the trees alive.

This page is for the friends group, school, club or municipality staff running a park or street tree planting day with volunteers. It covers sizes volunteers can plant, spacing, the planting method the arborists' bodies publish, the day itself and the two years after it. It draws on those bodies and on HortOS, a free directory of Canadian wholesale plant growers with their published availability and trade prices. Specifying and procuring trees covers the tree order itself.

Quick facts

Sizes for volunteers	Volunteers plant plugs to #15 containers and 50 mm calliper trees by hand. Larger trees need a contractor and machinery.
The hole	Two to three times wider than the root ball and only as deep, with the trunk flare showing, according to the International Society of Arboriculture.
Spacing	Space for the tree's mature canopy, not its size on the day. Small trees about 4 to 6 metres apart, large trees 10 metres or more.
Mulch	A ring of mulch a few centimetres deep, kept off the trunk. Never a volcano of mulch against the bark.
Aftercare	Deep watering through the first two summers, weeding inside the mulch ring, and stakes and guards removed on time.
Where the trees are	Growers listing trees are on the province hubs: Ontario, Quebec, British Columbia.

Sizes volunteers can plant

The size of tree decides who can plant it. Plugs to #15 containers and 50 mm calliper trees can be carried and planted by hand with a spade. Anything larger is heavy, needs a deep hole and usually a machine, and belongs to a contractor working beside the volunteers. Smaller trees also establish faster in a prepared site and cost far less, so a planting day gets more trees in the ground for the money.

The table lists trees often planted in parks and streets, with how many growers listed each on HortOS on 25 October 2026. Counts are the nurseries each plant's page on HortOS showed as growing it on 25 October 2026. Median trade prices are not published for Canada yet.

Of the trees in the table, white spruce (Picea glauca) had the most nurseries growing it, 38, and tamarack (Larix laricina) the fewest of those shown, 12. A tree many growers list is easier to order in numbers and to replace if it fails.

Choosing the trees

Choose trees for the site, not the day. A tree's mature height and spread, its tolerance of the soil, drainage and exposure, and how much water it will need once established decide whether it thrives. Natives suited to the district usually establish best and support local wildlife, and a mix of species protects a planting from losing every tree to one pest.

Ask the municipality's arborist or the landowner which species they want on the site, since many keep an approved list for parks and streets. Then check which of those species growers near the site list, in the sizes volunteers can plant, before fixing the plan.

Spacing and the site plan

Space trees for their mature canopy. A tree that will be ten metres wide planted four metres from the next will crowd it within fifteen years. Mark every planting spot on the ground before the day with a painted dot or a peg, set back from paths, roads and buildings, and away from overhead wires.

Underground services are the risk volunteers cannot see. Ask the municipality or the utility locating service for the area to mark pipes and cables before any hole is dug. Trees under power lines covers what may be planted near overhead lines.

Planting the tree

The International Society of Arboriculture's Trees Are Good guide says the planting hole should be two to three times wider than the root ball but only as deep. It says the trunk flare should be partly visible after planting, and that mulch should be 5 to 7.5 cm deep with a gap of 2.5 to 5 cm at the trunk. It also says trees develop stronger trunks and roots when they are not staked, so stakes are for windy sites and come out after the first year.

1. Find the trunk flare, where the roots spread from the trunk, and set it at or just above ground level.
2. Dig a wide, shallow hole, and loosen the sides so roots can grow out.
3. Tease out circling roots on a container tree, and remove any wrapping.
4. Backfill with the soil from the hole, firming gently and watering as you go to settle it.
5. Spread mulch in a wide ring, kept clear of the trunk.
6. Stake only on windy sites, with loose ties, and remove the stakes after the first year.

Running the day

Many planting days are run by municipalities working toward canopy goals; the City of Toronto, for example, aims for 40 per cent tree canopy cover by 2050 and holds public tree planting events.

• Brief in small groups. Show each group one tree planted correctly before they start. Ten volunteers watching one demonstration plant better than a hundred reading a sheet.
• Tools and water on site. Spades, gloves, a water source and buckets at each group, and the trees laid out at their spots before people arrive.
• Check every tree. Walk the row before people leave. A tree planted too deep or with mulch against the trunk is fixed in a minute on the day and dies if left.

The first two summers

Most losses happen in the first two summers. Agree before the day who waters, how often and with what. A deep soak once a week in dry weather is better than a sprinkle every day. Pull weeds inside the mulch ring, top up the mulch, and remove stakes and guards before they cut into the trunk. Planning a planting budget shows how to cost the watering.

Count the trees at the end of each summer. A simple survival count, with the dead trees marked on the site plan, tells the group how its method and watering worked, and which species to plant again. Replace losses in the next cool season from the same species that thrived, so the planting closes up evenly.

What to watch for

• Planting too deep. A tree buried past its trunk flare struggles for years. Find the flare before planting.
• Volcano mulch. Mulch piled against the trunk rots the bark. Keep a gap at the trunk.
• Big trees for a big day. Large trees look good in photographs and are hard for volunteers to plant well. Plant smaller and plant more.
• No watering plan. Trees planted and left die in the first dry spell. Name who waters before the day.
• Stakes left on. Ties left on for years cut into the trunk. Diary the removal.

Getting it right

1. Agree the site, the trees and the aftercare with the municipality or landowner, and have services marked.
2. Order plugs to #15 containers and 50 mm calliper trees from growers near the site, a season ahead.
3. Mark every planting spot for the mature canopy, clear of paths, wires and services.
4. Brief volunteers in small groups with a demonstration tree, and check every tree before they leave.
5. Mulch in a wide ring, stake only where needed, and water in deeply.
6. Water through two summers, weed the rings, and remove stakes and guards on time.

A word of caution

The planting method on this page is what the arborists' bodies named here publish, and the municipality's arborist or the landowner sets the rules for each site. The tree counts and prices are what HortOS printed on 25 October 2026, and the live pages change as growers update their lists.

Sources

• International Society of Arboriculture, Trees Are Good: planting a tree: planting depth, width and mulch.
• City of Toronto, Trees in Toronto: the city's canopy goal and programs.
• Canadian Nursery Landscape Association, Canadian Nursery Stock Standard: how nursery stock is sized.
• Communities in Bloom: community greening program.