Newly transplanted trees and shrubs have not extended their roots into the existing soil and therefore need adequate moisture to reach the root ball. Soil type and the amount of rainfall govern the amount of watering necessary. Water in the evening by filling the soil ring around the tree to the top. Never use a high pressure hose as it destroys the ring. Maintain the integrity of the ring throughout the season. If there is heavy rain, you can leave the tree for that day as long as the soil is wet. Once the tree is more established (usually a calendar year) you can remove the ring.
Depending on water flow rate, it is usually best to use a soaker hose system to water hedges. For the first season of planting, water along the roots for a minimum of 30 minutes, twice a day.
Greely Tree Services uses a commercial grade fertilizer with a ratio of 10-52-10 (nitrogen-phosphorus-potash). It promotes root growth in newly planted trees. We fertilize when planting and recommend that a similarly ratioed fertilizer be used every 4- 6 weeks thereafter following the manufacturer’s directions.
There are other watering methods available to suit personal preferences. Timers on hose systems can regulate watering. Water bags can deliver water deep below the soil surface with no run-off and require less frequent filling. Further options are easily researched on your chosen internet search engine.