The short version for Ottawa: prune most trees from December to March, with February into March the best window; plant deciduous trees by mid-October and pine or spruce by the end of September; remove dead wood and hanging limbs in any month; book a big removal for frozen ground if it can wait; and apply for a City permit about two months before you want a 30 cm-or-larger tree taken down, because the process takes weeks. Elms are closed to pruning from April 1 to September 30 and oaks from April through November. September is the poorest month on the calendar for structural pruning and one of the best for walking the yard and finding what the summer storms left behind. This page puts every date from our guides on one calendar. Each month links to the guide the fact comes from.
Ottawa tree care, month by month
Ottawa’s calendar is set by three things: the tree’s dormant season (roughly December to March, when the ground is frozen and the branch structure is visible), the two insect and disease windows that close elms and oaks to pruning for most of the growing season, and the storm pattern, which is summer thunderstorms followed by the first wet snow in November. Everything below follows from those three.
January
Main pruning season for most species, and the best month for a large removal. Frozen ground protects the lawn and root zone, so heavy equipment does far less damage than it would in October, and a bare crown is easier to read. A standing dead ash gets more expensive and more dangerous every winter it stands, so January is when we would rather take one down than clear it off a roof in a storm. Winter is also when emerald ash borer damage is easiest to spot from the street: woodpeckers strip the outer bark to reach the larvae and leave pale blonde patches on the trunk. Details in the pruning guide, the cost guide and the emerald ash borer guide.
February
The sweet spot for pruning, roughly February into March, before the buds move. A cut made now sits dormant for a few weeks and then gets closed on by a full season of growth. Almost nothing is moving in the way of fungal spores or bark beetles. Oaks are in their safe window (December to March) and elms are open (they close April 1).
March
Still the sweet spot for pruning and removals; taper off as the buds break, usually late in the month. Oak pruning ends this month. Ontario’s forest health reporting recorded a late-March ice storm across Eastern and Southern Ontario in 2025, so a heavy, wet late-winter load is possible and an already-damaged tree should not be left to wait for it.
April
Elm pruning closes on April 1 under the Canadian Food Inspection Agency’s Dutch elm disease guidance, and it stays closed until September 30, because the elm bark beetles that carry the fungus are drawn to fresh cuts. Oaks are closed from April through November as an oak wilt precaution. For everything else, pruning tapers off from late March through May. Broadleaf evergreens and yew that were held over the winter can be planted now.
May
Spring planting. Hydro Ottawa’s planting guidance is that trees under 6 metres at maturity go at least 1.5 metres from hydro poles; see the planting guide for the clearances and the species to avoid. This is also when tar spot and anthracnose infect maple leaves during wet weather, which is why a treatment offered in August cannot work: fungicides are preventive and go on at bud break. A permit application for a removal you want done in July should go in now, since the City’s process takes weeks rather than days.
June
Light pruning only from June through August. Late June into early July is the right time for a shaping cut on a cedar hedge, because you are cutting soft outer growth rather than opening wounds in structural wood; hedge work is the one job where summer is the right season. Watch irrigation: a newly planted tree that goes into the season dry is the one that does not come back.
July
Thunderstorm season. July 2026 was the rainiest month in Ottawa’s recorded history, at 318 per cent of normal rainfall, and Councillor Glen Gower’s forestry update of 24 July 2026 reported 755 storm-related service requests from July 1 to 5 alone. Hedge shaping continues into early July. If a limb is torn or hung up in a storm, that is same-day work in any month; the emergency page explains what counts as urgent and what a storm callout costs (1.5 times our published schedule).
August
Still storm season; the storm on the night of 12 August 2026 gusted to 107 km/h at the airport and damaged hundreds of trees across the city. August is also when maple leaves go black and spotty from tar spot infected back in May, and when door-to-door crews turn up after every storm: ask for a broker-emailed insurance certificate and a written quote, and remember that anything signed at the door can be cancelled within 10 days under Ontario’s Consumer Protection Act. Apply now for any permit you want in hand for an October removal.
September
The month to skip for structural pruning, for two reasons: the tree is shutting down rather than building tissue, so a wound sits open through a wet fall and a freeze-thaw winter before anything closes it, and early autumn is peak season for decay and canker fungi releasing spores. Dead wood, hangers and split unions are still fine to remove now, and they are the most useful thing to deal with before winter. Plant pine and spruce before the end of the month while the soil is warm. Walk the property for what August left behind: hangers, torn stubs, fresh cracks, and any lean that is newer than you are sure about, with cracked or heaved soil on the upslope side of the base. Elms reopen to pruning on October 1.
October
Deciduous planting deadline is about mid-October, which gives at least six weeks to establish before the ground freezes. Elm pruning reopens (October 1). Rake and remove maple leaves with tar spot or anthracnose, because both fungi overwinter in the litter and reinfect from below in spring. Tight clusters of honey-coloured mushrooms at a trunk base, usually seen in fall, are worth a photo to us: they are likely Armillaria, which is actively killing roots. See the mushrooms guide. A crown thinning on a dense conifer or Norway maple before the first snow costs a fraction of an emergency callout after it.
November
First wet snow and freezing rain. This is the load that finishes the branches the summer storms cracked, which is why a tree that stood through every thunderstorm comes apart in a quiet November snowfall. Cedar hedges bend open at the top under wet snow and do not close, because cedar does not regrow from brown wood. Oak pruning reopens in December; structural pruning on everything else can start once the leaves are down and the tree is dormant. See the wet snow guide.
December
Main pruning season opens (December to March), including oaks. Removals get easier as the ground freezes. Emergency, after-hours and storm callouts are 1.5 times our published schedule all year; regular work is booked at the regular schedule with a $160 + HST minimum on any job, per the pricing page.
Jobs that do not follow the calendar
- Dead wood, hanging limbs and immediate hazards come out in any month. A hung-up limb caught in the canopy is same-day work.
- Stump grinding is priced from a photo, often the same day, with no site visit needed; the schedule is on the pricing page ($250 for a stump up to 30 cm across at the root flare, rising to $1,190 at 100 cm).
- Quotes are free in every month. We reply within 24 hours; for tree work Max comes out in person and the written quote follows within 48 hours of that visit.
- Permits take weeks, not days, so the calendar for a planned removal of a tree 30 cm or more across inside the urban boundary starts about two months before the date you want. Dead trees, immediate hazards and ash killed by emerald ash borer are exempt under By-law 2020-340; photograph the tree before anyone cuts. Which neighbourhoods are inside the rule is on the by-law by neighbourhood page.
Quick answers
When is the best time to prune trees in Ottawa?
December through March, while the tree is dormant, with February into March the sweet spot: the tree is weeks from pushing growth, so a cut sits dormant briefly and then gets closed on by a full season of growth, the structure is visible with the leaves off, and almost nothing is moving in the way of fungal spores or bark beetles. Two species are strictly winter jobs by rule: elms cannot be pruned from April 1 to September 30 (a federal Dutch elm disease measure) and oaks should not be cut from April through November (oak wilt). Light pruning of a healthy tree from June to August is fine, and dead wood, cracked limbs and anything left hanging by a storm can come out in any month, ideally before the first wet snow in November. September is the month to skip for shaping or thinning a healthy tree: the tree is shutting down, not building, so the wound sits open through a wet fall and a freeze-thaw winter, and autumn is when decay and canker fungi are releasing spores. Hedges are the exception, cut in late June or early July.
What is the best month to prune trees in Ottawa?
February into March, for most species. The tree is dormant, the branch structure is visible with the leaves off, frozen ground protects the lawn, and cuts made then are closed on by a full season of growth starting a few weeks later. The wider window is December to March.
Is it too late to plant a tree in Ottawa in the fall?
Deciduous trees need about six weeks to establish before the ground freezes, so get them in by mid-October. Pine and spruce should be planted before the end of September while the soil is still warm. Broadleaf evergreens and yew are better held until spring.
When can I prune an oak or an elm in Ottawa?
Elms: not between April 1 and September 30, under the Canadian Food Inspection Agency’s Dutch elm disease guidance, so an Ottawa elm waits until October. Oaks: not from April through November as an oak wilt precaution, which puts oaks in a December-to-March window. Storm damage on either is dealt with when it happens, not by the calendar.
Is tree removal cheaper in winter in Ottawa?
Marginally easier rather than much cheaper. Frozen ground protects the lawn and root zone, and a bare crown is easier to read, but the price is set by the tree’s size, what it is standing over and how we get at it. Typical residential removals run $500 to $2,500 in any season; emergency and storm callouts are 1.5 times the schedule.
When do I apply for a tree permit if I want the tree down this fall?
About two months ahead. The City’s distinctive-tree permit process takes weeks rather than days and may come with a replanting or compensation condition, so a removal you want done in October should be applied for in August. The permit is $174 per tree; dead trees, immediate hazards and EAB-killed ash are exempt.
When are the signs of emerald ash borer easiest to see?
Winter, on an Ottawa street, is when woodpecker blonding shows best: pale patches where the outer bark has been stripped to reach the larvae. Crown dieback from the top down and leafy shoots low on the trunk show during the growing season, and by the time dieback is obvious from the driveway the tree has usually been infested for two to three years.
Dates on this page are the windows we work to in Ottawa and are drawn from our guides, which cite the Canadian Food Inspection Agency, the Invasive Species Centre, Hydro Ottawa, the City of Ottawa and university extension services; they are not a substitute for looking at the tree. Prices are from our published 2026 schedule and exclude 13% HST.
Have a dead or dying ash? See dead ash tree removal in Ottawa: $500 to $2,500 while the tree can still be climbed, a bucket or crane at cost after two or three winters standing dead, no City permit for a dead or borer-infested ash (photograph it first), and why the wood cannot leave the Ottawa–Gatineau regulated area.
Taking wood to the cottage this fall? Read what the federal firewood rule actually says for Ottawa: moving ash firewood out of the CFIA’s emerald ash borer regulated area is prohibited all year, cottage trips included; non-ash firewood can only leave the area through a CFIA-approved facility, so a private household has no legal route out with any species; yard waste is under the same rule; but most of eastern and central Ontario (Renfrew, Lanark, Frontenac, Leeds and Grenville, the Kawarthas, Muskoka) is inside the same regulated area as Ottawa, so most cottage trips never cross the line.
Heard the spotted lanternfly has reached Ontario? Read what the federal record actually says about Ottawa: the first live detection in Canada was Windsor on 15 September 2026; Ottawa’s only entry is one dead insect intercepted in January 2023; significant damage has only been observed on grapes, not maples; and September–October is when egg masses (grey putty, later cracked mud) get laid on trunks, vehicles and patio furniture.
Worried the wet summer hurt your trees? Read which Ottawa trees mind waterlogged soil and which do not: standing water for a week or less is harmless, the weeks of airless clay afterwards are not; spruce, sugar maple and oak are the ones to watch, silver maple and honeylocust will not have noticed, and the damage usually shows next May, not this fall.
Planted a tree this year, or took one of the City’s free ones? Read what actually kills a newly planted tree in an Ottawa winter: it is the strap left around the trunk, mulch piled against the bark and rabbits in March, not the cold — and after this wet summer, check the soil before you water.