"Working with James was great from the beginning. He put my mind at ease with his product knowledge and his creative designs."
Hardscaping · Markham, GTA
Natural Stone Patios in Markham.
Astonia Landscaping designs and builds high-end residential landscapes and natural-stone masonry in Markham. Owner James Dennison is a third-generation stonemason, and Astonia has been doing this work since 1975. Every Markham project is owner-led, built by our own WSIB-covered crews with our own equipment, and backed by $5 million in liability insurance. We are a Unilock Authorized Contractor.
- Since 1975
- 3 Generations
- $5M Insured
- WSIB Covered
- Unilock Authorized
In Markham
Landscaping that belongs in Markham.
Markham holds two very different kinds of property under one municipality, and a stone landscape has to answer to both. In Unionville and along the older heritage streets near Main Street, you have established homes on mature lots where the architecture and the streetscape already have a settled character — work here calls for restraint, natural stone that reads as if it has always been there, and detailing that respects the age of the house rather than competing with it. In the executive enclaves of Cachet and Angus Glen, the homes are larger and newer, the frontages more generous, and the expectation is a designed, cohesive landscape that matches the scale of the architecture. We design for the property in front of us, not a template.
Many of these are established executive homes on settled lots, which usually means mature trees, finished grading and existing hardscape that a new build never has to work around. Protecting healthy specimen trees, tying new stonework into established planting, and matching the grade and drainage already in place takes more planning and more care than a blank site — and it is exactly the kind of work that benefits from owning our own equipment and running our own crews, so there are no subcontractor delays and no guesswork on a property where mistakes are visible for decades.
Markham homeowners making a once-in-a-generation investment in their property tend to value the same things we do: craft that lasts, a clean and respectful site, and direct communication with the person responsible for the work. James is on your project and reachable every day. We haul all debris away in our own trucks — no bins parked on the driveway of an established street — and we leave the site tidy each evening, because in a settled neighbourhood the condition of the site matters as much as the finished result.
What we build
Natural Stone Patios, start to finish.
Natural Stone Patios
Interlock Patios
Walkways
Retaining Walls
Steps & Coping
Driveways
The craft
Built from the ground down.
A natural-stone patio is the part of a landscape you live on. It carries the table, the chairs, bare feet in summer and snow load in winter, and it has to hold its line through every freeze and thaw for decades. That is why we build from the ground down before we build up. Most patios fail at the base, not the surface, so we excavate to the right depth for the soil we find, lay and compact a graded aggregate base in lifts, and grade for drainage that moves water away from the house. The stone you see is the last decision, not the first.
Within hardscaping we lay flagstone and full-depth natural-stone patios, interlock in the formats and finishes that suit the architecture, walkways that connect the property without feeling like a path bolted on, and steps cut and set to a comfortable, consistent rise. We build retaining walls that are engineered to hold grade rather than just dress it, set stone coping that finishes a wall or pool edge cleanly, and lay driveways meant to carry real weight. James is a third-generation stonemason, and the difference shows in the joints, the cuts around a curve, and the way a level run of coping reads from across the yard.
Material choice is where a patio is won or lost, and it is rarely about price. Natural stone — flagstone, granite, limestone, full-stone treads — ages and weathers in a way no two installs repeat, and we help you weigh it against quality interlock, where we are a Unilock Authorized Contractor working with warranty-grade product. We talk through colour, format, finish and how each option lives with your home, your grade and your climate before anything is ordered. The goal is a surface that looks intentional in year one and still looks right in year twenty.
The work runs on our own equipment and our own crews, which is why the site stays tidy and the schedule holds. There are no subcontractor gaps waiting on someone else's machine, and no bin parked on your driveway for weeks — all excavation spoil and demolition debris leaves in our trucks, every day. James communicates daily from the first site visit to the final sweep, the crews are WSIB-covered, and the company carries $5 million in liability insurance. You get the build quality of a large outfit with the accountability of the person whose name is on the work.
How it works
From first handshake to final reveal.
01
Initial Consultation
We meet you on-site to walk the space, understand how you want to live in it, and talk through your vision and investment — no obligation.
02
Design & 3D Review
Our designer measures and plans your space, then renders it in 3D so you can see it before we break ground. We refine every detail together.
03
Breaking Ground
Our own crews and equipment start at 7:00 AM, keep the site clean every day, and brief you each morning and evening — no subcontractor gaps, no bins.
04
Project Completion
After a final walkthrough, the only thing left behind is your finished space — built to gather on for generations.
The Astonia difference
Why homeowners in Markham choose us.
Owner-led
Daily communication from James, from the first handshake to the final reveal.
Our own equipment
Small and heavy machines, run by our own crews — no subcontractor delays.
No unsightly bins
We haul every bit of debris away in our own trucks, every day.
$5M insured
Liability coverage above the industry average, for your peace of mind.
WSIB covered
A fully covered, professional crew on every project.
Unilock Authorized
Warranty-grade materials and professional installation standards.
Kind Words
Homeowners across the GTA, on the Astonia experience.
Five decades of referrals across the GTA & Durham — and a Unilock Authorized Contractor. Read more on Google & Houzz.
"The natural stone work and landscape job that James and his crew did is beautiful, outstanding work. The quality is outstanding — we would recommend this company to anyone."
"Astonia was a delight from start to finish. The crew showed up early and worked long days to finish on time. We are now enjoying the most amazing front yard. Outstanding results!"
"As a repeat client, we selected Astonia to transform our simple backyard into a relaxing space amongst a natural setting that will bring us many years of pleasure."
Good to know
Natural Stone Patios in Markham, answered.
Not when the base is built correctly, which is most of the work you never see. We excavate to the proper depth for your soil, compact a graded aggregate base in lifts, and grade for drainage so water moves away rather than pooling and freezing under the stone. A patio fails from the base up, so that is where five decades of experience earns its keep.
Both can be the right answer depending on the home, the grade, the budget and the look you are after. Natural stone — flagstone, granite, limestone — weathers with character no two installs share; quality interlock offers consistency and a wide range of formats, and as a Unilock Authorized Contractor we build it with warranty-grade product. We walk you through colour, format and finish against your specific space before anything is ordered.
We design and build across the GTA & Durham region — including Toronto, Etobicoke, Mississauga, Brampton, Oakville, Vaughan, Markham, Newmarket, Aurora, King City, Whitby, Oshawa, Bowmanville and the surrounding areas.
Every project is different — from focused stonework to a full landscape transformation — so we provide a clear, detailed proposal after an on-site consultation rather than a generic price. Most of our work is a meaningful, lasting investment in your property.
Timelines depend on scope, and you receive a realistic one at the design-review stage before we break ground. Because we own our equipment and run our own crews, we work efficiently — starting at 7:00 AM and keeping the site clean every day.
Yes. We carry $5 million in liability insurance — above the industry average — our crews are fully WSIB covered, and we are a Unilock Authorized Contractor.
More services in Markham
Natural Stone Patios nearby
Natural Stone Patios in Markham, done right.
Book a free on-site consultation. We design, build and plant the whole space — then haul it all away when the last stone is set.
$5M insured · WSIB-covered crews · 3rd-generation craftsmanship since 1975