There are two primary types of true lemons, Eureka, which produces an open, thornless tree, and Lisbon, which produces a dense, thorny tree. Eureka lemons originated in California and are the less seedy of the two; they produce most of their fruit in the spring and summer. Lisbon lemons come to maturity in summer and fall. The Meyer lemon is a hybrid that produces a fruit less acidic than that of a true lemon, and can be grown in containers. Lemon tree care is minimal and they are hardy in USDA planting zones 8 through 11.
Water the tree every three days for the first two weeks after planting. Continue to irrigate once a week for the remainder of the first growing season unless there has been sufficient rain. For the second and subsequent growing seasons, water every other week unless there has been no rain and the weather is hot and dry.
Wrap a piece of heavy duty aluminum foil around the young trunk from the ground to the scaffold branches. This will protect it from sun scorch and contact herbicides, if you use them for killing weeds or as a weed killer in your lawn.
Hand-pick or use a contact herbicide to keep weeds from around the tree. Keep at least a 3-foot diameter around the trunk free of weeds at all times. Do not spray the herbicide within 4 inches of the trunk. Follow the manufacturer's directions on how to use herbicides properly.
Apply a citrus tree fertilizer once you see some growth the first year and every spring thereafter. Spread the fertilizer on the surface of the ground in a 3-foot diameter around the tree and water it into the soil. Follow the manufacturer's directions on amount to use for the size and age of the tree.
Spread a 2-inch layer of organic compost over the root system of the tree in the summer. Regular watering will leach the compost into the soil and provide needed nutrients. The compost will also help to retain moisture in the heat of the summer.
Cover the tree with a blanket by wrapping it if there is danger of frost in the northern areas of the planting zone. You can buy wraps at garden centers to protect trees from frost.