Growing citrus trees and other subtropical fruits is a fun, easy experience in warm-winter climates. The plants are attractive and bear healthy, delicious fruits. Check out our guide to growing citrus and subtropical fruits in your yard!Climate
Every subtropical fruit has its own climate preference based on daytime temperatures, humidity, and rainfall, as well as a low-temperature limit, so do your homework before planting to ensure you have the right fruit for area.
Four main climates are suitable for growing citrus and subtropical fruits: tropical, semitropical, subtropical, and temperate climates.
Tropical climates have abundant rainfall, high humidity, and no distinct seasons, with warm temperatures occurring throughout the year.
Semitropical areas have high annual rainfall and humidity with recognizable seasons. Summers are hot and winters are warm with occasional cold spells.
Subtropical regions see great variations from one another. They can be hot and dry with relatively warm winters, or rainy with frosts common.
Temperate areas have well-defined seasons and are typically too cold in the winter months to grow subtropical fruits outdoors all year. But you can bring plants indoors during the snowy season.
You can sometimes cheat a little on climate. For example, planting next to a light-color wall maximizes the amount of heat during the day; planting next to a dark wall will keep it warm at night. Siting plants against walls like this may allow you to be successful with varieties that would struggle or die in the middle of your yard. In general, if you want maximum heat, plant on the south or west side of your home.Plant Selection
Subtropical plants are sold in two ways: container or bare root. Field-grown bare-root plants are usually pruned to compensate for roots lost during digging and don't have the full appearance of plants grown in containers. Both will do well once in the ground -- just be sure not to keep them in their nursery pots for long.
When picking plants, look for healthy specimens that show active growth. Avoid plants that have yellowed leaves, dead branches, or large, circling roots near the soil surface of the pot. You can plant container-grown varieties anytime as long as they are kept moist prior to and after planting. Bare-root plants are dug while dormant and sold with their roots packed in sawdust. When selecting a bare-root plant, look for a well-formed system with roots extending in all directions and avoid plants with damaged or dry roots. Keep bare-root plants cool and moist, and be sure to plant as soon as possible.Planting
For healthy growth, plants need three things from soil: moisture, nutrients, and air. Some types of soil, such as clay or sand, provide less-than-ideal conditions. However, adding compost or other organic materials loosens and aerates clay while helping sandy soil hold moisture and nutrients better. If your soil has a hardpan or other impervious layer below the topsoil, organic matter will not improve the drainage. In such cases, it's best to plant in containers or raised beds.
It's also important to know the pH (measure of acidity or alkalinity) of your soil. Soil pH affects the availability of plant nutrients. Most subtropical fruits grow best in slightly acidic soils, but many tolerate slightly alkaline conditions, especially if they are given foliar feedings of micronutrients. To test pH, purchase an inexpensive kit available at most nurseries and scientific supply houses. Many cooperative extension services also perform soil tests and can provide more data than a kit, including soil texture and nutrient content. Soil amendments (soil sulfur to add acidity; lime to add alkalinity) are available in most nurseries to balance pH.
Also, be aware of the salt level of your soil. High salts can occur from irrigation water or fertilizer residues, or can be natural in certain soil types. Symptoms of salt damage can range from slow growth to leaves with burnt edges. If you suspect high levels of salt are damaging your plants, leach the soil by watering deeply every third or fourth irrigation. Well-drained soil is necessary for successful leaching. If your soil is both salty and poorly drained, grow citrus and subtropical fruits in raised beds or containers.
To plant container-grown plants, dig a hole at least twice as wide as the root ball, but to a depth that allows the top of the root ball to sit slightly above the grade of the surrounding soil. Gently remove the root ball from the container. Loosen matted or circling roots by raking through them with your fingers or a trowel or cultivator. Position the tree in the hole and check the depth of the root ball by placing the shovel handle across the hole. Adjust the depth of the hole if necessary. Fill the hole with existing backfill soil. Create a watering basin over the top of the root ball by mounding soil in a ring. Water the root zone thoroughly. Fill the moat created by the ring of soil.
To plant bare-root plants, dig a hole at least twice as wide as the root ball and to a depth that allows the plant to sit slightly above its original planting depth (look for a color change along the trunk). Prune away damaged or tightly wound roots. Spread out the roots in the bottom of the hole. Work the backfill soil between and around the roots, firming it as you go. Create a watering basin over the top of the root ball; water thoroughly. Planting in the spring, after the threat of frost is over, will ensure that your citrus or subtropical fruit plant will become established before the winter.Watering
There are several ways to water citrus and subtropical fruit plants -- in basins, by sprinklers, or with a drip system. Soil basins can simplify watering and are easy to construct. Once you know how deep 1 inch of water will penetrate, adjust the height of the basin walls or the number of times you fill the basin to allow your plant an adequate water supply. For sprinklers, match the application rate of the sprinkler to the soil's ability to absorb water and be sure that it doesn't wet the trunk. Note: Sprinklers that apply water too fast can cause erosion and wasteful runoff.
Drip systems discharge water at very low rates, usually between 1/2 and 1 gallon per hour, to a precise area, eliminating evaporation and waste. A young tree needs at least four emitters evenly distributed beneath its canopy. A modified drip system, called trickle irrigation, can provide low-volume (5-50 gallons per hour), low-pressure mini sprinklers, which emit a fanlike spray with a radius of 3 feet or more. The larger coverage area wets the root zone more evenly, and the larger orifices of the mini sprinklers are less susceptible to clogging.Fertilizing
Just as with soil and water, fertilizer type depends on your specific plant. Be careful with application: Too much fertilizer causes more damage than too little. Because fertilizers are salts that leave acidic or alkaline residues, excessive use can burn plants and alter pH. A soil test is the best way to determine exactly which nutrients are available in your soil and which fertilizer to use.
For safe application, apply fertilizers three or four times during the growing season, beginning in late winter and ending in late summer. Fertilizing after late summer can delay dormancy in subtropical plants and increase the chance of damage from sudden cold weather in the fall. Light feeders need little or no fertilizer, but for other subtropical fruits, apply 1 to 2 tablespoons of a complete fertilizer three or four times during their first two growing seasons. From the third to the eighth year, gradually increase the feedings from 1/4 to 1 pound of actual nitrogen per year. From the ninth year onward, give plants between 1 and 1-1/2 pounds of actual nitrogen per year.Pruning
Pruning isn't necessary for most citrus and other fruits, but you may consider it to control size, to control appearance, or to stimulate new growth and heavier yields.
If you do prune, there are two types of pruning cuts: thinning and heading.
Thinning cuts remove branches or limbs where they join the rest of the plant. This results in a more open plant. By thinning main shoots back to shorter side branches, you can decrease the size of a plant without destroying its natural character.
Heading cuts remove the terminal or top of a branch. This results in vigorous growth from dormant buds just below the cut and a denser, more compact plant. Shearing to form a hedge is a type of heading. Both thinning and heading control the size of a plant, but thinning usually produces a healthier, more attractive plant.Controlling Disease
When plants are properly cared for, they resist insects and diseases. So the best advice for controlling pests is to prevent problems by growing the right plant in the right place. Drought-stressed, improperly planted, or over-fertilized plants are more susceptible to pest and disease problems than vigorously growing plants.
If your plant does become infested or infected, use only a chemical approved for your specific plant and follow label directions precisely. Pay attention to how close to harvest a spray can be safely applied. Pest-control regulations vary from state to state -- if you have questions, consult you cooperative extension service.