The answer to 'how to maintain tree' is to regularly prune, water, and fertilize your trees. Proper tree maintenance helps keep them healthy, promotes growth, and prevents safety hazards. Start by pruning your trees annually to remove dead, damaged, or overgrown branches. Use clean, sharp tools and make cuts just outside the branch collar to avoid damaging the tree. Next, water your trees deeply, about 1-2 times per week during dry periods, to a depth of 12 inches. Fertilize in early spring with a balanced, slow-release fertilizer to provide essential nutrients. Monitor your trees for signs of pests or disease and address issues promptly.
If you have large or mature trees, or are unsure about proper techniques, it's best to consult a certified arborist for professional tree care. They can assess the health of your trees and provide expert maintenance recommendations.