Plant Selection and Horticulture
This domain tests whether you can match a plant to its site and keep it alive: hardiness and heat zones, soil pH and drainage, nomenclature, nursery specification, and correct planting technique.
Right plant, right place
USDA cold-hardiness zones set minimum winter temperature; AHS heat zones set summer stress. Both matter, and microclimate (south-facing wall, low frost pocket, reflected heat from pavement) can shift the effective zone by one. Test soil pH, texture and drainage. Most landscape plants perform at pH 6.0-7.0; rhododendron, blueberry and pin oak need acid soil, while lilac and clematis tolerate alkaline.
Nomenclature and specification
Genus and species are italicized; cultivar names sit in single quotes and are not italicized, as in Acer rubrum 'October Glory'. Specify caliper for shade trees (measured 6 in above grade), plus height, spread and root type (B&B, container, bare root).
Planting
Set the root flare at or slightly above finished grade. Amend backfill lightly, water to settle, and mulch 2-3 in deep, kept clear of the trunk. Expect roughly one growing season of establishment per inch of caliper.
Worked example
A 2,500 sq ft bed on a triangular grid at 5 ft on center: each plant occupies 0.866 x 5 squared = 21.7 sq ft, so 2,500 / 21.7 = about 116 plants. The same bed on a square grid at 5 ft takes 100. The count changes with the pattern, so state the pattern on the plan and on the order.
Traps
Treating a zone rating as a guarantee rather than a probability; reading drought tolerant as needing no water during establishment; planting too deep and burying the flare; italicizing cultivar names; and specifying species that are invasive in the region.