Grow Your Own Citrus
Grow Your Own Citrus: Easy Tropical Trees
© Tara A. Spears
Citrus trees are actually evergreen shrubs; retaining the majority of their leaves year-round as long as they are in frost-free regions. Indigenous to tropical climates that have abundant rainfall, high humidity, and no distinct seasons- with warm temperatures occurring throughout the year- citrus fruits have long been coveted as a source of vitamins besides for its taste.
Although some citrus, mainly lemons and limes, can flower all year long, the majority of flower production occurs in late February through March. Interestingly, a mature citrus tree can produce hundreds of thousands of blossoms, yet two percent or less of these blossoms result in edible fruit. This heavy blossom production is nature’s way of assuring that insects, attracted by the tree’s fragrance, pollinate the maximum number of flowers possible.
Depending on the variety, a citrus tree is capable of producing anywhere from 1 to 1000 pounds of fruit per season. Maximum yields will vary according to variety, weather conditions, cultural care, age of tree, and many other factors. Fortunately, the fruit from citrus trees doesn’t mature in the span of a few weeks as deciduous trees do. In fact, citrus trees generally hold their fruit for a three to four month time period after they are first considered palatable, thereby allowing harvesting to occur over a period of time without a loss of taste and nutrients.
If you wish to enjoy homegrown citrus, plant different varieties with different ripening periods to ensure fresh citrus for up to nine months a year. Some experts suggest that citrus fruits do not improve in flavor after they are picked. Others agree that an acid reduction and color change may occur and lead to a milder flavor if held a few days after they are picked. All agree that citrus should be allowed to ripen on the tree. In fact, if the fruit stays longer on the tree, it will get slightly sweeter and less acidic. Essentially, citrus are fully ripe when they have reached the color, size, and flavor as specified for their type. All types of citrus juice freezes quite well.
Citrus trees make nice specimen trees in the yard, thrive in pots, and the fragrance of their blossoms is an intoxicating patio enhancement. Once happily established, a citrus tree will reward you with years of abundance. You might find yourself with so many citrus fruits you’ll be giving them to everyone you know! Growing a citrus tree isn’t that hard as long as you provide the tree with the conditions it requires to flourish. Of all the citrus trees, limes are probably the most cold sensitive-they don’t like temperatures below 50 degrees F/ 10 degrees C.
Planting and Placement: For healthy growth, citrus plants love full sun and 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. I find the local horses that are tethered around the neighborhood to be a great source of natural amendment; mixing in horse mature is an excellent addition to the local sandy soil. If your garden soil has a hardpan or other impervious layer below the topsoil, organic matter will not improve the drainage. Most of the Guayabitos lots have been filled, and therefore are heavily rock laden. In such cases, it’s best to plant your citrus tree 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 nutrients. Soil amendments that balance pH (soil sulfur to add acidity; lime to add alkalinity) are available in most agricultural supply stores.
Also, be aware of the salt level of your soil. High salt content can occur from proximity to the ocean, besides being carried by irrigation water or fertilizer residues. 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 deep soaking the tree about every fourth watering.
To plant container-grown citrus trees, 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 by filling the moat created by the ring of soil with water.
Warning: It’s all about Drainage. It’s imperative to plant your lime tree in an area that has proper drainage. If you plant your tree in an area prone to standing water, the tree is likely to die. Though lime trees like regular water, they don’t like standing in it. A good way to test the soil’s drainage capabilities is to dig a hole 1 foot wide and 2 feet deep. Fill the hole with water and allow it to drain out and then fill the hole with water again. If the water is gone within 24 hours or less, the drainage is great. If it takes two days for the water to drain out of the hole, the area will be acceptable for planting your lime. If it takes more time than 48 hours for the water to drain out of the hole, forget about planting your lime tree there- plant the lime into a large pot.
Fertilizing: Determining how much you use and what type of fertilizer, just as with the soil amending, depends on your specific plant’s requirements. 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. For safe application, apply fertilizers three or four times during the growing season, beginning in late winter and ending in late summer, so now it the time to fertilize in the Riviera Nayarit. I use the time-release granules because they are readily available in the area at the Thursday tianguis and local plant nurseries also carry this fertilizer. For citrus 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 isn’t necessary for most citrus plants, 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. I do this type of pruning a couple of times a year to make harvesting ripe fruit easier. 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.
Alas, a Citrus Villain: Canker Disease. The green areas on the map are high concentrations of citrus canker disease. If your citrus plant shows sign of citrus bacterial canker, the only sure cure it to cut down the tree and burn it. According to US Department of Agriculture, Dr. T.R. Gottwald, “ The causal agent of CBC has been identified as Xanthomonas axonopodis bacteria that is spread by wind or water dispersal in order for populations to move to new hosts. When rain is driven by significant winds (the summer stormy season), the rate of disease typically increases.”
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; or cut and burn infected fruit tree.