Organic Frost Protection
Frost-sensitive lime trees experience fruit damage below 30 (-1.1°C), although they usually recover to produce new fruit the following year. Organic frost-protection measures include:
- Growing them in containers where winter temperatures regularly drop below 30°F, and moving them indoors until spring.
- Growing them in containers where frost is rare and moving them close to a south-facing wall in winter. The reflected heat should warm them enough to stay outdoors.
- Watering in-ground trees slowly and deeply and covering them with frost blankets when frigid weather is on the way. Freezing soil robs the roots of moisture.
Until they put out new leaves, water your recently planted limes deeply two or three times weekly. When their roots have established, soak them only when the top 2 inches of soil feel dry.
Expert gardener’s tip: Testing the soil with an inexpensive soil moisture meter available at your garden supply store prevents unnecessary watering.
Begin fertilizing when the trees have six or more inches of new growth. Use granulated, slow-release, organic 5-2-6 fertilizer. It provides a steady stream of nutrients over a long period, so you can fertilize less often.
Fertilize in late winter or early spring, mid-summer and early fall at the following rates:
- Trees up to 3 feet tall: 6 cups (1.3 liters)
- Trees between 3 and 6 feet: 12 cups (2.6 liters)
- Trees between 6 and 9 feet: 18 cups (4 liters)
- Trees over feet: 24 cups (5.3 liters)
Spread the fertilizer evenly in a circle at the ends of the branches and water it in.
Fertilizing Potted Lime Trees
Give potted limes 1 teaspoon of fertilizer for every 4 inches of pot diameter, up to 12 inches. Double the amount for larger pots.
Expert gardener’s tip: To compensate for water-leached soil nutrients, fertilize potted limes every two months from late winter until early fall.
Prune lime trees in late winter or after your last spring frost. Take only the dead, diseased, damaged or crossing branches. Prune suckers from around the base of the trees as soon as they sprout.