Decorative Rock in Brooklyn Park.

Single-family detached housing covers more than 40 percent of the city's land, so most properties are conventional lots with straightforward access. Flatter through the west, falling toward the Mississippi River bluff along the eastern edge.

The city is not one kind of ground. Along the eastern edge the land falls toward the Mississippi, and properties on that side are dealing with genuine slope, faster runoff, and soil that moves if it is left bare. West of there it flattens out into conventional suburban lots where water sits rather than runs. The same job on those two sides of Brooklyn Park is two different jobs, and the estimate should reflect that rather than a city average.

Lots here are generously sized and most of them are not irrigated, which means full-sun areas take the summer hard. Turf that looks healthy in June goes dormant and thin by August in the open parts of a large Brooklyn Park lot, and the usual reaction is to reseed the same ground and get the same result. Where an area is simply too exposed to hold grass without watering, converting it to bed or rock is a better answer than an annual reseed.

The east side near the river bluff drains earlier in spring than the flatter west side, which can put two Brooklyn Park properties a fortnight apart on when work can start. That is a real difference within one city, and it means a start date quoted from the address rather than from the property is a guess.

Homeowners here routinely underestimate the removal side of a project. An overgrown front bed that looks like an afternoon's work produces several truckloads once it is actually out of the ground, and the disposal is frequently the largest single line on the estimate. Knowing that before starting is the difference between a project that finishes and one that stalls half-cleared.

We work throughout Brooklyn Park, including Riverview, Willowstone, Zane North and Oak Grove Parkway, and around Zane Avenue and Highway 610. Two properties on the same street can still need different work — which is exactly why the estimate is free and done in person rather than quoted off a photograph.

Most rock beds we are asked to look at here already exist and have failed — grass growing through, fabric shredded, edging buried. Renovating properly means the old rock comes up before the new goes down.

• Long-lasting finish
• Lower routine upkeep
• Defined bed lines
• Many color and size options

Rock installed badly is far more expensive to fix than mulch installed badly, because getting it out is a removal job. The classic failure is stone laid straight onto soft ground with no edge and no base: within a few seasons it has pressed down into the soil, grass has grown up through it, and half of it is in the lawn where the mower finds it. The second failure is fabric. Everyone expects fabric to stop weeds forever; what actually happens is that dust and leaf litter build a thin soil layer on top of it, weeds root happily in that, and now they are growing through a sheet that has to be torn out.

Rock is sold by weight and it is heavy, so both the material and the labour to move it scale quickly with area. Depth of excavation, the length of edge to be set, and whether existing material has to be hauled away are usually the three numbers that move the estimate most.