Most struggling trees in the west GTA are not diseased, they are starving and compacted. Subdivision soils in Brampton, Milton, and Mississauga were stripped and graded before the houses went in, and the trees planted afterward sit in a thin layer of topsoil over compacted clay, with lawn fertilizer feeding the grass and road salt loading the root zone every winter. Plant health care starts with figuring out why a tree is thin, off colour, or dying back, then treating the actual cause. Deep root fertilization is often part of the answer. We inject a slow release fertilizer solution into the root zone under pressure, typically 15 to 30 cm down on a grid pattern under the canopy, which feeds the roots directly and fractures compacted soil as it goes. It works on anything from a 3 metre serviceberry to a 25 metre mature maple. We pair it with a proper look at the whole tree, mulching, watering habits, girdling roots, soil condition, and pest pressure, before recommending anything. If your tree just needs a cheaper fix, like a mulch ring and a hose schedule, we will tell you that instead of selling injections.
What's included
- A walkaround diagnosis of the tree and its site, looking at crown density, leaf colour and size, dieback pattern, trunk condition, soil, drainage, and planting depth before anything gets injected.
- Deep root fertilization by pressurized soil injection on a grid under the canopy and just beyond the dripline, placing slow release nutrients 15 to 30 cm down where the feeder roots actually are.
- A slow release, low salt fertilizer blend chosen for the species and the deficiency, not a one size fits all cocktail.
- Soil condition notes covering compaction, grade changes, salt exposure, and organic matter, with plain language recommendations for mulching and watering.
- Inspection for common west GTA pest and disease pressure, including emerald ash borer in ash, tar spot and verticillium symptoms in maples, and scale on lindens and honey locusts.
- A frank recommendation when fertilization is not the fix, for example a buried root collar or a girdling root, and a quote for the work that would actually help.
- A written summary of what was applied, what we found, and what to watch for over the following season.
How it works
- Call or email with photos of the tree and a note about what changed. Thinning crown, early fall colour, and dead tips all point to different causes.
- On site assessment and free written quote. We diagnose first and price the treatment plan, whether that is fertilization alone or a combination of work.
- Treatment visit. Injections take under an hour for most single trees, and we work around gardens and irrigation lines.
- Follow up guidance. You get written notes on watering and mulching, since injections without aftercare waste your money.
- Reassessment the following season where warranted, so we can see whether the crown responded before recommending a repeat.
What the free estimate covers
- The number and size of trees being treated. Injection grids scale with canopy area, so one mature silver maple can take as much product and time as five young street trees, and multi tree visits price better per tree.
- What the diagnosis turns up. The free estimate assesses whether fertilization is even the right treatment. If the real problem is a girdling root or construction damage, we quote that work instead.
- Soil condition. Heavily compacted clay in newer Brampton and Milton subdivisions takes more injection points and more pressure time than an established Etobicoke garden with decent soil.
- The product the tree needs. A standard slow release feeding differs in cost from treatments targeting a specific deficiency, such as chlorosis in maples and oaks on high pH soils.
- Access and site layout. Trees inside fenced yards, on slopes, or far from where we can park the rig take longer to treat than open front lawns.
- Whether a treatment program makes sense. Some stressed trees benefit from spring and fall visits over two or three seasons, and we price the program honestly up front rather than surprising you visit by visit.
Free Estimate, quoted in writing before any work starts.
On-site visit, written quote, no obligation. Usually within 24 hours of your call.
When you need this
- Your maple's crown is thinning from the top down, leaves are smaller than they used to be, or fall colour arrives weeks early. Those are classic root stress signals in Norway and silver maples across the west GTA.
- A tree near a new driveway, addition, or pool is showing dieback a year or two after construction. Compaction and root loss show up on a delay, and feeding plus soil work can help what is left recover.
- Your street lost its ash canopy to emerald ash borer and you want the remaining trees on the property kept vigorous rather than stressed into vulnerability.
- A newly bought home in Mississauga or Oakville came with mature trees planted in lawn to the trunk, mower scarred and never fed. A mulch ring and a feeding program is cheap insurance on trees the whole street benefits from.
- Leaves are yellowing between green veins, especially on maples and oaks. That chlorosis pattern is common on the high pH clay soils across Halton and Peel and responds to targeted treatment.
- Cedars or spruce are browning from the inside out after a hot dry summer, and you want to know whether it is normal flagging, mites, or drought stress before you replace them.
Local notes for the west GTA
There is no permit involved in feeding a tree, so this is one service where municipal bylaws stay out of the way. The local context that matters is soil and species. Most of our plant health care work in Brampton, Milton, and Mississauga is on trees planted into graded subdivision clay, where compaction, shallow topsoil, and road salt do more damage than any insect. In older Toronto and Etobicoke neighbourhoods the usual pattern is mature maples in the 60 to 100 year range that have never been fed, growing in lawns that get grass fertilizer but nothing at root depth. Keeping a stressed tree alive is also the cheaper path. Once a large tree dies, removal in Toronto generally involves a permit above 30 cm trunk diameter measured at 1.4 metres, and replacement plantings take decades to give back the shade. A feeding program costs a small fraction of a large removal, which is the honest math behind most of the work we do in this category.
Where we provide this service
Frequently asked questions
How much does deep root fertilization cost? +
We price it as a Free Estimate because tree count and canopy size drive the number. A single young tree is quick. A property in Oakville with six mature maples is a half day with a lot of product. The on site estimate is free and in writing, and it covers the part that matters more than the price, which is the diagnosis. Many of the fertilization calls we take turn out to be something else, a buried root collar, a girdling root, drought stress, or simple mower damage, and injecting fertilizer into those trees would do nothing. You get our honest read on the cause first, then a price for the treatment that fits it, whether that is a feeding, a different service, or just a watering schedule that costs you nothing.
When should trees be fertilized in Ontario? +
Early spring and mid to late fall are the two best windows. In spring the tree takes up nutrients as it pushes new growth, and in fall the roots keep working long after the leaves drop, storing reserves for the following year. Fall feeding is underrated and is often the better choice for stressed trees because nothing is forced. What we avoid is heavy feeding in mid summer heat and drought, which can push tender growth at the worst time, and late summer applications that encourage growth too soft to harden off before frost. If your tree is visibly declining, do not wait months for the perfect window. We would rather assess it now and time the treatment properly than have you watch another season of dieback.
Will fertilizing save my declining tree? +
Sometimes, and it depends entirely on why the tree is declining. Fertilization helps trees that are nutrient starved or recovering from stress with an intact root system. It does not cure emerald ash borer, it does not fix a girdling root that is strangling the trunk, and it will not compensate for roots cut during construction. This is why we diagnose before we treat. A tree in early decline from soil and nutrient problems can rebound noticeably within a season or two of feeding, mulching, and proper watering. A tree in late decline, with major deadwood and bark falling off the trunk, is usually past help, and we will say so and talk about removal before the tree becomes a hazard over your house or your neighbour's yard.
Is deep root fertilization better than lawn fertilizer or spikes? +
For trees, yes. Lawn fertilizer is formulated for grass, applied at the surface, and mostly intercepted by turf roots before tree roots see it. It is also high in fast release nitrogen, which is not what a stressed tree needs. Fertilizer spikes concentrate nutrients in a few spots and reach only the roots that happen to sit near a spike. Pressurized soil injection places a slow release blend throughout the root zone at the depth feeder roots actually occupy, usually the top 30 cm, and the injection process itself opens channels in compacted clay, getting air and water down where west GTA subdivision soils rarely allow. It is the difference between feeding the tree and feeding the lawn and hoping.
My maple's leaves have black spots. Does it need treatment? +
Probably not, and this is one of the most common calls we get from Toronto, Etobicoke, and Mississauga every August. Black spots the size of a thumbprint on Norway and silver maple leaves are tar spot, a fungal disease that looks alarming and does very little real harm to the tree. Spraying is rarely justified. Raking and disposing of fallen leaves in autumn reduces next year's spores, and that is genuinely the best control. What we pay more attention to is whether the crown behind the spots is healthy. If the tree also has thinning, dieback, or undersized leaves, the tar spot is a distraction from a root or soil problem worth diagnosing. Send photos and we will tell you which situation you have before you pay anyone for a treatment you do not need.
Do you treat trees for emerald ash borer? +
If you have a surviving ash, the honest picture is this. Emerald ash borer has killed most untreated ash across the GTA, and an ash that still holds a full healthy crown is worth a conversation about protective injection treatment, which runs on a repeating cycle and is something we assess and quote as part of a plant health care visit. An ash that has already lost a third or more of its crown, with woodpecker damage and D shaped exit holes in the bark, is generally past saving, and the practical conversation is removal before it becomes brittle and dangerous to work on. Dead ash fail unpredictably, so we flag those early. Either way, the assessment costs nothing and you will know which side of the line your tree is on.