Bailey Acacias do not usually need watering except when they're first planted, in time of drought, or in late fall before the ground freezes for the winter. If you do water, give your plants 1 gallon of water twice a week or run your drip irrigation system or sprinkler for 20 minutes twice a week. Older shrubs need watering only during severe drought.
For more information see file on Caring for Trees.
These shrubs need only one yearly application of bagged sludge, a slow-acting granular fertilizer with a slow release form of nitrogen, or compost. In the fall, spread a fertilizer on the soil to 1-1/2 times the distance from the trunk to the tips of the branches, If the distance is 20 feet, then fertilize 10 feet beyond the tips of the branches (drip line). You may wish to supplement the fall feeding with 2 or 3 monthly snacks in late spring and early summer. Use a light side dressing of fertilizer or apply a foliar spray of dilute liquid fertilizer over all the leaves of the plant.
For more information see file on Choosing Fertilizer.
A layer of organic mulch should take care of any serious weed problems. If you don't mulch, be careful with weeding tools, to avoid damaging the shrub's root system. It's best to hand-pull weeds growing close to the shrub. Hard-to-kill perennial weeds can be controlled by spot-treating with a fatty acid soap herbicide or a glyphosate herbicide, both of which are biodegradable. It's best to consult with your local Cooperative Extension agent for latest recommendations.
If you do not mulch, cultivate lightly beneath the trees with a hoe to control weeds, that might otherwise compete with the acacia's root system for nutrients.
For more information see file on Using Mulch.
Acacias don't need pruning, but by cutting out the central leader, you can train a young plant to grow into a shrub; removing lower branches encourages your acacia's natural tendency to grow into a tree. Cut out some of the interior branches from older trees, to reduce dieback and avoid risking wind damage.
For more information see file on Pruning Shrubs.
For more information see file on Choosing Pruning Tools.