Why the first year is different
A nursery plant arrives with its entire root system packed into the volume of its pot. Until those roots grow out into the surrounding soil — which takes a full season for perennials and one to three years for trees and shrubs — the plant can only drink from that small root ball, even when the soil a few inches away is moist.
That's why "drought-tolerant" labels don't apply in year one. Drought tolerance describes an established plant; everything needs consistent moisture while it establishes.
Deep and infrequent beats shallow and daily
A light daily sprinkle wets the top inch of soil and trains roots to stay shallow, where they cook in summer and dry out fastest. A slow, deep soak once or twice a week pushes water down eight to twelve inches and pulls roots down after it.
For trees and shrubs, lay the hose at the base on a trickle for twenty to thirty minutes, or use a five-gallon bucket with small holes drilled in the bottom. For beds, a long pass with a wand at soil level beats anything sprayed over the leaves.
Check before you water
The finger test is still the best moisture meter: push a finger two inches into the soil at the edge of the root ball. Damp means wait; dry means water. Overwatering kills as surely as drought — roots sitting in saturated soil suffocate, and the wilting that follows looks exactly like thirst, which tempts people to water more.
Mulch is the multiplier on every watering: a two-to-three-inch ring of wood-chip mulch (kept off the trunk) cuts evaporation dramatically and evens out the wet-dry swings that stress young roots.