# Landscaping and lawn care in Thornhill

URL: https://hotivlandscaping.ca/areas/thornhill/  
Updated: 2026-10-13  
By: Hotiv Landscaping, Markham, Ontario. Call or text (437) 684-2535.

**Short answer:** Thornhill is one community split between two cities: east of Yonge Street is Markham (postal codes starting L3T) and west of Yonge is Vaughan (L4J). We do landscaping and lawn care on both sides, including sod, cleanups, hedge trimming, interlock repair and deck and fence work. The watering, tree and yard waste rules differ between the two halves, so we've set them side by side below.

Thornhill has been split down Yonge Street since it was settled in 1794. Before 1971 the Township of Markham ran the east half and the Township of Vaughan the west half. Today it's the City of Markham and the City of Vaughan, both in York Region, Ontario.

For landscaping and lawn care, that split decides which by-laws apply. Two houses a few hundred metres apart can have different watering hours, a different grace period for new sod and a different leaf pickup schedule. People usually draw Thornhill's edges at Dufferin St to the west, Highway 7 to the north, Highway 404 to the east and Steeles Ave to the south, where Toronto starts.

## Which side of Yonge are you on?

East of Yonge is Markham and west of Yonge is Vaughan. Postal codes are a quick check: L3T is the Markham side and L4J the Vaughan side. If you're not sure, your property tax bill names the city.

| Rule | Markham side (east of Yonge) | Vaughan side (west of Yonge) |
|---|---|---|
| Lawn watering season | June 1 to September 30 | May 15 to September 30 |
| Lawn watering hours | 6 to 9 a.m. or 6 to 9 p.m., not both | 6 to 9 a.m. and 6 to 9 p.m. |
| Watering days | Odd or even days to match your house number | Odd or even days to match your house number |
| Grace period for new sod and seed | Two months | One month |
| Private tree permit | Trunk 20 cm or more across, measured 1.37 m up | Trunk 20 cm or more across, arborist report with most applications |
| Yard waste containers | Kraft paper bags or open rigid containers, under 18 kg each | Kraft paper bags, or open-top rigid containers up to 121 L marked for yard waste |
| Yard waste pickup | Every other week, April 7 to October 30 in 2026 | Weekly in spring and fall, every other week in summer |
| Fence height | 1.2 m in the front yard, 1.8 m along side and rear lot lines | 1.2 m in a front yard within 2.4 m of the street, 2.0 m for most other fences |

Watering rules are from York Region's summary of each city's by-law. The rest comes from each city's own pages, listed under Sources. The cities' pages are the final word, so check them before you plan around a date.

## How long can you water new sod in Thornhill?

York Region lists a two-month grace period for new sod and seed on the Markham side and one month on the Vaughan side. New sod needs far more water in its first few weeks than an established lawn, and that's what the grace period is for.

In practice, a Vaughan-side lawn laid in early summer goes back on the normal schedule sooner, while it's still rooting. The trade-off is that Vaughan's normal schedule allows both the morning and the evening window, where Markham allows only one.

Sod laid in late August or September has an easier time on either side than sod laid in July. Penn State Extension notes that sod laid in summer needs more frequent watering and takes longer to establish. Our guides on the [best time to lay sod in Ontario](https://hotivlandscaping.ca/guides/best-time-to-lay-sod-ontario/) and [how often to water new sod](https://hotivlandscaping.ca/guides/new-sod-watering-care/) go into the details. The [sod installation](https://hotivlandscaping.ca/services/sod-installation/) page covers the job itself.

## Do you need a permit to remove a tree in Thornhill?

Yes, if it's a private tree with a trunk 20 cm (about 8 inches) or more across, on either side of Yonge. Markham measures the trunk 1.37 m above the ground. Vaughan asks you to confirm the tree's size and ownership and, for most permit types, get an arborist's report before you apply.

Vaughan also has a separate permit for removing or injuring a tree because of work on a residential property, such as changing a driveway or walkway. Both cities count injuring a tree, not only cutting it down. Digging a new garden bed or relaying a patio over the roots of a big maple can fall under that, so ask the City first if the work is close to a large tree.

South of Steeles, in Toronto, the private tree threshold is 30 cm. Our [North York page](https://hotivlandscaping.ca/areas/north-york/) covers Toronto's rules.

## When is leaf and yard waste pickup in Thornhill?

On the Markham side, pickup runs every other week from April 7 to October 30 in 2026. Material goes in kraft paper bags or open rigid containers, each under 18 kg. Branches under 15 cm across go in tied bundles under 1.2 m long. Grass clippings aren't collected.

Vaughan collects weekly from late April and again in the fall, and every other week through the summer (from the week of June 9 in 2026). In 2025 its last fall pickup was in early December, well after Markham's ends. Vaughan takes kraft paper bags, or open-top rigid containers up to 121 litres marked for leaf and yard waste, at the curb by 7 a.m. The City mails out yard waste stickers on request. Neither city takes plastic bags, and Vaughan's waste calendar has this year's exact weeks.

That difference changes how you time a [fall cleanup](https://hotivlandscaping.ca/services/seasonal-cleanup/). On the Markham side, the bags need to go out on your last pickup day before October 30. Our [fall cleanup checklist](https://hotivlandscaping.ca/guides/fall-cleanup-checklist/) has the rest.

## How high can a fence be in Thornhill?

On the Markham side, a fence can be 1.2 m (4 feet) in the front yard and 1.8 m (6 feet) along the side and rear property lines. On a corner lot, the street side is held to 1.2 m.

On the Vaughan side, a front yard fence within 2.4 m of the street can be 1.2 m high, and most other residential fences can be 2.0 m. Vaughan's by-law counts a hedge that acts as a fence, so a hedge in that strip of front yard is held to 1.2 m too, which matters when you book [hedge trimming](https://hotivlandscaping.ca/services/hedge-trimming/). The by-law has more cases, such as fences next to a driveway or a public walkway, so check its table before you replace a fence.

Repainting or repairing an existing fence doesn't change its height. [Fence painting and staining](https://hotivlandscaping.ca/services/fence-painting-staining/) and [deck and fence repair](https://hotivlandscaping.ca/services/deck-fence-repair/) don't run into these limits. Our guide on [fence height rules in Markham and Toronto](https://hotivlandscaping.ca/guides/fence-rules-markham-toronto/) has more.

## Heritage rules in old Thornhill

Both halves of the old village are heritage conservation districts. The Markham half is one of four in Markham, along with Unionville, Markham Village and Buttonville. There, the City lists new or changed driveways, front walkways, front yard patios, new or different fences and painting as work that needs a heritage permit. Planting, general repairs (fences included) and back yard patios that can't be seen from the street don't.

The Vaughan half is one of Vaughan's four districts, along with Kleinburg-Nashville, Maple and Woodbridge. Vaughan asks for a heritage permit for any work that changes how a property looks.

If you want to change the front of a property in the old village, talk to your city's heritage staff before booking anything. [Interlock repair](https://hotivlandscaping.ca/services/interlock-repair/) that relays the same pavers in the same layout is a much smaller change than a new driveway design, but it's still worth a quick call to check.

## Landscaping quotes in Thornhill

We're based in Markham and work on both sides of Yonge, from [lawn care](https://hotivlandscaping.ca/services/lawn-care/) and sod to interlock and deck work. Put your postal code in the message: L3T or L4J tells us straight away which city's watering, tree and pickup rules the job runs under. [Text it with a couple of photos](sms:+14376842535?&body=Hi%20Hotiv%2C%20I%27d%20like%20a%20quote.%20Here%20are%20some%20photos%20of%20the%20area%3A) to [(437) 684-2535](tel:+14376842535), or use the form below, and we'll arrange a free visit. Further out, see our pages for [Markham](https://hotivlandscaping.ca/areas/markham/), [Vaughan](https://hotivlandscaping.ca/areas/vaughan/) and [Richmond Hill](https://hotivlandscaping.ca/areas/richmond-hill/).

## Neighbourhoods in Thornhill we work in

We also work in Royal Orchard, Bayview Glen, Thornhill Woods, Brownridge.

### Old Thornhill

The old village grew up around Yonge St between Centre St and John St after it was settled in 1794, and it takes its name from Benjamin Thorne, who arrived in 1820 and ran mills there. Yonge runs right down the middle, so half the village answers to Markham and half to Vaughan. Both halves sit in heritage conservation districts, so a new or changed driveway, front walk or fence needs a heritage permit on either side. Repairs are simpler. Markham doesn't need a heritage permit for general repairs or planting, and Vaughan says repairs to property features usually don't need a heritage review, so fixing an old walkway, trimming hedges and clearing leaves from big, old trees can go ahead as normal.

### German Mills

German Mills sits on the Markham side, along the Don Mills Rd corridor north of Steeles Ave, where Leslie St breaks. Most homes are single-family houses, many built in the 1970s and 1980s, so original driveways, patios, decks and fences can be 40 or more years old. German Mills Settlers Park, 26 hectares of former sand pit and landfill, is part of the neighbourhood. On lots this age, interlock that has sunk or heaved, faded decks and tired foundation plantings tend to need work around the same time.

### Uplands

Uplands takes its name from the Uplands golf course, a Stanley Thompson design that opened in 1922. The course lost about half its land to housing development in the 1980s, and the Uplands Ski Centre opened on part of the rest in 1989. The houses built on that land are now around 40 years old, an age when the first interlock, the original sod and the back deck often need attention together.

## Postal codes in Thornhill

Thornhill addresses have postal codes starting with one of these:

- L3T: Thornhill east, the Markham side (shared with Markham)
- L4J: Thornhill west, the Vaughan side (shared with Vaughan)

## What we do most in Thornhill

- [Sod installation & lawn repair](https://hotivlandscaping.ca/services/sod-installation/)
- [Interlock repair & paver leveling](https://hotivlandscaping.ca/services/interlock-repair/)
- [Spring & fall cleanups](https://hotivlandscaping.ca/services/seasonal-cleanup/)
- [Hedge & bush trimming](https://hotivlandscaping.ca/services/hedge-trimming/)
- [Polymeric sand & weed removal](https://hotivlandscaping.ca/services/polymeric-sand-installation/)
- [Lawn mowing & lawn care](https://hotivlandscaping.ca/services/lawn-care/)
- [Deck staining, sealing & waterproofing](https://hotivlandscaping.ca/services/deck-staining/)

## Questions from Thornhill homeowners

### Is Thornhill in Markham or Vaughan?

Both. Thornhill isn't a city of its own. Yonge Street divides it: the east side is in the City of Markham and the west side is in the City of Vaughan. Postal codes starting with L3T are generally on the Markham side and L4J on the Vaughan side. Your property tax bill says which city you're in, and that city's by-laws apply to your yard.

### How long can I water new sod in Thornhill during watering restrictions?

It depends on the side of Yonge. York Region lists a two-month grace period for new sod and seed in Markham and one month in Vaughan. Outside the grace period, Markham allows watering 6 to 9 a.m. or 6 to 9 p.m. (not both) from June 1 to September 30, and Vaughan allows both windows from May 15 to September 30, on odd or even days to match your house number.

### Do I need a permit to remove a tree in Thornhill?

On either side of Yonge, a private tree with a trunk 20 cm or more across needs a permit before it's removed or injured. Markham measures it 1.37 m above the ground. Vaughan asks for an arborist report with most applications. South of Steeles you're in Toronto, where the private tree threshold is 30 cm.

### Do I need a heritage permit for a new driveway in old Thornhill?

Probably, on either side of Yonge. Thornhill is a heritage conservation district in both Markham and Vaughan. Markham lists new or changed driveways, front walkways, front yard patios and new fences as work that needs a heritage permit, and Vaughan asks for one for any work that changes how the property looks. Talk to your city's heritage staff before you book the work.

### Do you work in Thornhill?

Yes, on both the Markham and Vaughan sides. We're based in Markham, which takes in the east half of Thornhill. Send your postal code through the quote form or text (437) 684-2535 with your street, and we'll arrange a visit for a free quote.

## Sources

1. [Wikipedia: Thornhill, Ontario](https://en.wikipedia.org/wiki/Thornhill,_Ontario)
2. [Wikipedia: German Mills](https://en.wikipedia.org/wiki/German_Mills)
3. [York Region: Outdoor water use by-laws](https://www.york.ca/OutdoorWaterUse)
4. [City of Markham: Water use by-law](https://www.markham.ca/about-city-markham/city-hall/bylaw/water-use)
5. [City of Markham: Tree permit application](https://www.markham.ca/neighbourhood-services/trees/tree-permit-application)
6. [City of Vaughan: Tree removal permits and protection](https://www.vaughan.ca/residential/parks-and-trees/forestry-operations/tree-removal-permits-and-protection)
7. [City of Markham: Yard material collection](https://www.markham.ca/neighbourhood-services/recycling-garbage/yard-material)
8. [City of Vaughan: Leaf, yard and Christmas tree waste](https://www.vaughan.ca/residential/garbage-and-recycling/leaf-yard-and-christmas-tree-waste)
9. [City of Vaughan: Biweekly leaf and yard waste collection starts next week (June 2, 2026)](https://www.vaughan.ca/news/biweekly-leaf-and-yard-waste-collection-starts-next-week-0)
10. [City of Vaughan: Leaf and yard waste collection ends this week (December 2, 2025)](https://www.vaughan.ca/news/leaf-and-yard-waste-collection-ends-week-1)
11. [City of Markham: Fences and swimming pools](https://www.markham.ca/about-city-markham/city-hall/bylaw/fences-swimming-pools)
12. [City of Vaughan: Fences](https://www.vaughan.ca/residential/by-laws-and-enforcement/property-by-laws/fences)
13. [City of Markham: Heritage districts](https://www.markham.ca/economic-development-business/planning-development-services/zoning-and-development-law-information/heritage-protection/heritage-districts)
14. [City of Markham: Heritage permit](https://www.markham.ca/economic-development-business/planning-development-services/planning-and-development-applications/heritage-permit-he)
15. [City of Vaughan: Heritage conservation districts](https://www.vaughan.ca/residential/building-and-construction/building-permits/cultural-heritage-preservation/heritage-conservation-districts)
16. [Penn State Extension: Lawn management through the seasons](https://extension.psu.edu/lawn-management-through-the-seasons)
17. [City of Toronto: When to apply for a tree or ravine permit](https://www.toronto.ca/services-payments/building-construction/tree-ravine-protection-permits/when-to-apply-for-a-tree-or-ravine-permit/)
18. [Wikipedia: List of postal codes of Canada: L](https://en.wikipedia.org/wiki/List_of_postal_codes_of_Canada:_L)
19. [Wikipedia: List of postal codes of Canada: M](https://en.wikipedia.org/wiki/List_of_postal_codes_of_Canada:_M)
20. [Canada Post: Find a postal code](https://www.canadapost-postescanada.ca/cpc/en/tools/find-a-postal-code.page)