Growing Key Lime / Mexican Lime Trees in Northeast Florida Landscapes
(Citrus aurantifolia)
Origin of Key Lime / Mexican Lime Lime For Northeast Florida:
Although the parentage of the Keylime is unknown, it is believed to be a cross between three separate citrus genera Citrus medica, Citrus maxima (grandis), and Citrus micrantha. It was brought to Ameica by the Spanish an dPortugese explorers in the early 1500’s where it became naturalized in the Carribean and East coast of Mexico and tropical areas of South America and the Florida Keys. Although key limes are no longer grown commercially in Florida, it remains a beloved “Florida” fruit.
Winter Temperature Tolerance For Key Lime / Mexican Lime:
Key Limes can be grown in tropical and subtropical climate zones successfully in zones 8-11 so they are an ideal candidate for a Northeast Florida food garden. Winter temperatures from 30-32°F can damage leaves and soft stems and temperatures below 30° can damage tree supporting structures and trunk et. Protect young and newly planted trees from and hard freeze in your area and cover during a hard freeze if needed.
Sun Exposure for the Key Lime / Mexican Lime Tree in Northeast Florida:
Plant Key Lime trees where they will receive full sun in the Jacksonville and St. Augustine area landscapes. They require 6 hours of direct sunlight or more for best production.
Blooms and Key Lime / Mexican Lime Trees for Northeast Florida Landscape:
Blooms of the Key Lime / Mexican Lime tree are small, 5 petaled, white fragrant blossoms that are born in clusters on new growth, like other citrus they are extremely fragrant. Key lime trees will bloom heavily in the early spring and you will find blossoms intermittently throughout the year although the subsequent blooms will be much lighter than the spring blooms.
Citrus trees are self pollinating, so there is no need for a second tree to pollinate your tree in order for it to produce fruit.
Key lime fruits are oblong to rounded and much smaller than a grocery store lime, 1.5-2 inches in diameter. The peel is thin and smooth and turns a soft green to yellow when mature. Pulp is also a faintly greenish tinged yellow with 10 or more seeds per fruit. Think of them as single serve packages of limey goodness perfect proportions to cover that taco, or to add to your cup of iced tea.
Soil Preference for the Key Lime / Mexican Lime Tree:
It is no longer a recommended practice to amend the soil in the planting hole on Citrus trees in good soil according to the University of Florida’s Institute of Food and Agricultural Sciences. However, probably due to the simple fact that old habits die hard, one UFIFAS citrus publication cautions, if you are going to amend your soil be sure to use a 50-50 ratio. In other words, use equal parts soil amendment and native soil (that is the soil you dug out of the hole before placing the tree in it), and mix the amended soil together with the native soil before back filling the hole around the tree.
Size of the Persian Lime / Tahiti Lime | Bearss Lime Tree When Mature:
The mature size on a Persian Lime / Tahiti Lime tree is 10-12ft tall and 6-8 ft wide when grafted onto trifoliate rootstocks in Florida. Dwarf selections may be found grafted onto Flying Dragon rootstock.
Pruning and Growth Habits of Key Lime / Mexican Lime Lime for the Northeast Florida Landscape:
– Remove suckers that sprout up from the trunk, or to remove dead wood that can cause problems when left on the tree.
– When purchasing trees from an S & J Nursery container less than a 30 gallon pot size, pruning may be needed to shape the young trees into a desirable framework. In addition light pruning each year to develop the lemon trees rounded or mushroom shaped canopy, eliminate crossing or damaged branches etc.
-As the tree matures it should be shaped by selecting 3 – 5 main branches, well spaced along the trunk for fruiting production. Remove branches with narrow angles, and sub branches that are crossing or rubbing on other branches or branches / stems heading into the center of the tree should be removed as well.
Planting and Mulching Tips For Key Lime / Mexican Lime Trees in the Jacksonville | St. Augustine area landscape:
NOTE: THIS IS IMPORTANT
-Be sure to plant into well draining soils, and keep the soil level of the dirt in the container above the soil level of the ground by 1-2 inches when you are finished planting. The soil that your tree was growing in should be slightly higher or level with the ground.
– Never bury the top of the root system with soil ( the dirt in the pot that the tree was growing in). The soil in the top of the pot should be exposed to the air after planting, not buried by soil in any way.
Caution: Do not build berms around Citrus to hold water, as is recommended for pretty much all other trees. Leave a 12 inch diameter area around Citrus tree trunks with no mulch, do not put mulch up to the trunk of the tree on Citrus Root rot can develop quickly and good drainage is essential to a healthy tree.
Remove the grass and weeds growing under the foliage of any Citrus tree in Northeast Florida about a foot beyond where the foliage stops. Don’t allow grass and weeds to regrow under your Florida Citrus.
When planting in areas with a high water table, consider planting your Citrus into a raised berm a few feet high and 6 or more ft wide. This will keep your Citrus roots up out of the water soaked ground during periods of heavy rain.
Wow, that was allot of don’ts! Here’s one last one. Don’t worry, it really isn’t as hard as it seems, once you get them going Citrus trees just keep on growing!
So for all those “DONT‘s” listed above I have just two “DO‘s”for you that is additionally as critical for the long term success of your plant…
DO mulch under and around your citrus trees with Oak leaves, even if you have to beg some of of your neighbors. UFIFAS is recommending the practice to help deter the Asian Citrus Psyllid insect that is responsible for spreading Citrus Greening from tree to tree.
DO fertilize your tree with Citrus specific fertilizer. Key limes are a different genus of Citrus and don’t require as much fussing with fertilizer as other Citrus trees may but still need a good balanced Citrus fertilizer application once a season for best growth in Florida’s sandy soils.
Keeping your Key Lime / Mexican Lime Tree Free from Pests and Diseases:
When it comes to gardening, an ounce of prevention is worth a pound of cure. That is to say that, paying attention to proper planting, watering and fertilizing practices for your citrus tree is the best way to keep it healthy and growing well.
Water Requirements of the Key Lime / Mexican Lime in the Jacksonville and St. Augustine area Landscape:
Newly planted citrus trees require watering every other day for the first month and twice a week for the first few months, or in sandy soils when the top two inches of soil is dry to the touch. Take care to make sure that newly planted citrus trees receive water at least once a week for the first 2 years after being planted, skipping watering altogether once the local rain season is here.
Mature citrus trees need little to no supplemental irrigation in Northeast Florida’s subtropical climate zones and are more often damaged by over watering than under watering.
When citrus trees need supplemental irrigation, make sure to irrigate the soil only and not the trunk or foliage, this is best done by hand with a hose.
Harvesting your Key Lime / Mexican Lime Fruits straight from your very own tree:
Key Lime / Mexican Lime will be ready for harvesting fresh from your tree at differing times throughout the year due to their ever blooming habit. The fruit is ready approximately 4-9 months after it blooms. Now remember above how we mentioned that Key Limes flower heavily in spring but lightly throughout the year…yep that’s right, you can have key limes year round any time on your tree! Just harvest whenever the fruits have reached size and are showing that beautiful buttery yellow color to their peel or begin to drop from the tree after a storm!
Other Great Citrus Trees available at S & J Nursery for the Northeast Florida, Jacksonville | St. Augustine Area Gardens
Mandarin Orange, Satsuma Tangerine