Dwarf Lime Trees are relatively easy to grow. They generally only reach 2 - 3 feet in height and produce normal full size, green limes. in addition to being aesthetically appealing and pleasantly fragrant in an indoor setting, lime trees can provide years of tasty fruit.
They keys to successfully growing limes indoors are basically the same as with all citrus , good light, adequate temperature and humidity , well-drained potting soil, proper nutrients, and consistent moisture. Without any single one of those elements, failure looms.
Lime trees are generally container-grown, and purchased online or from a local nursery. They can also be propagated at home from cuttings, and seed. If you decide to grow Lime Trees from seeds, allow the seeds to dry out for up to two weeks. Once dried, plant the seeds about an inch deep in good potting soil and cover with plastic wrap. Once the seed has germinated it should be placed in a sunny location. Any container used for Lime trees and any indoor fruit trees, should provide ample drainage and room for growth.
Lime trees can be put outdoors during the summer months, this is recommended to increase their chances of bearing abundantly. When grown indoors they do not have the advantage of pollinators, bees and other insects. Placing them outdoors during the summer allows for this. You can also hand pollinate them.
See Indoor Pollination
Prune as necessary to shape the tree. Pruning will also encourage new branch development, and create a more compact and appealing shape. Lime trees that don't get enough light can become spindly and unhelathy. Should this occur, prune about 1/3 off the top growth and place the tree in a sunnier location or under grow lights
Limes require 8-12 hours of sunlight daily to prosper, 5-6 hours to just survive . Grown indoors, a South or west facing window is best . Not that I'm comparing apples to oranges, but citrus plants unlike other fruits do not normally go through a period of dormancy or hibernation in the winter, but will tolerate slightly lower light conditions during this phase of slower growth.
Supplemental light , such as grow-lights or fluorescent plant lights will help them produce better, especially if your location is not optimally sunned.
Night time temperatures no lower than 55°F and daytime temperatures around 70 - 80°F are ideal. They will usually tolerate temperatures hovering above 32 degrees for a few hours or heat over 100 degrees so long as they are well watered. Temperatures should however , not be a major problem in an indoor environment. Temperatures below 55 will will invoke a dormancy , extended periods below 55 could result in their premature demise.
You should be using a light [low clay], well draining soil mixture with an abundance of peat, and perlite or vermiculite. Adding addition perlite or vermiculite to any soil you purchase is advisable. You can also add wood chips, redwood shavings or even hamster bedding and semi-sterile compost [Not from your back yard compost heap] in moderation . Using dirt from your yard is a bad idea.
Lime trees will benefit from a mildly nitrogen rich or balanced NPK fertilizer. Micro-nutrients such as copper, zinc ,magnesium, manganese, iron, and boron. They prefer an acidic soil, so an acidic fertilizer can also be beneficial in citrus tree fertilizing, though not absolutely essential. Fertilizer developed specifically for citrus trees is naturally best.
Water regularly to keep the soil moist, not saturated, just moist. A layer of decorative sterile mulch such as bark or any other organic mulch is advisable to retain soil moisture. Allow the potting soil to slightly dry between watering, not "DRY-OUT" just slightly dry.
I prefer to water modestly 2 - 3 times weekly , test the soil by hand - stick your finger in about a half inch to be certain it is semi dry before adding more water. Over watering is just as deadly as under watering.
In winter months, artificial heat dry the air so plants will need added humidity. Misting the Lime trees foliage with a simple spray bottle is good way to help citrus cope with the indoor environment in winter. You can also add moisture with a humidifier, or by placing them, containers and all on a pebble filled tray with water added to the top of the pebbles.
Lime trees are susceptible to spider mites, mealy bugs and scale. Check the trunk for mealy bugs and scales. To treat spider mites, spray your plant with insecticidal soap or horticulturist oil, which will smother the insects. clean the foliage, top and bottom sides of the leaves as well. Neem Oil is effective against Scales and Mealy bugs. Rubbing alcohol applied with a Q-tip will also work in mild infestations.