Eureka lemon trees produce lemons throughout the year in warm climates, but most of the lemons ripen in the late winter, spring and early summer. Eureka lemon trees grow vigorously and have a spreading, open canopy. This variety of lemon tree has little cold tolerance and is nearly thornless. New growth and flowers are tinted with purple shades. The fruit develops in clusters on the outside of the canopy. The Eureka lemon is medium-small and oval shaped. The fruit is used as flavouring in food.
Locate your Eureka lemon tree in a site with good-drainage. This type of lemon tree adapts to nearly any soil types but heavy clay. Plant the tree on the south or southeast side of any buildings to help protect it from cold. The site needs to be in full sunlight and higher than the surrounding ground. Before planting, wash some of the potting medium from the root ball to expose some of the root tips. This improves the contact between the roots and the soil.
Build a ring around the tree out of soil that is 24 inches across and several inches thick. Fill the ring with water and let it soak in. Repair the soil ring when needed. Water the Eureka lemon tree every three days for three weeks after planting, then decrease the watering schedule to every seven to 10 days.
Pull any weeds and grass in the 24-inch circle around the Eureka lemon tree. This citrus tree does not grow well with any vegetative competition. All the available soil nutrients and moisture must go to the lemon tree for it to survive.
Feed the Eureka lemon tree with ammonium sulphate 21-0-0 four times a year. Use 1/4 cup each time for the first year, 1/2 cup for the second year and 3/4 cup for the third year. Scatter the fertiliser on the ground around the base of the lemon tree and water immediately.
Harvest the fruit when the skin turns yellow. The flesh of the Eureka lemons is pale greenish-yellow. These fruits do not have many seeds and are very acidic. Only pick when the fruit is dry.
Keep mulch 12 inches away from the trunk of the Eureka lemon tree. Mulch does not benefit the tree much and tends to promote root rot.
Do not pick unripe lemons. Citrus fruit does not ripen any further after picking. Eureka lemons are normally ripe in the spring and early summer.