Citrus Growing Guide

Seeing ripe citrus fruits hang like bright zesty ornaments from their branches in late fall and winter is surely a pleasing sight.  And now with summer on the horizon there’s nothing better than enjoying the fruit harvests by sipping on a nice refreshing glass of OJ or Lemonade under the heat of the sun. 

Even though most Citrus trees prefer warm sunny climates outside (Zones 9 or above), they can still be appreciated by being brought indoors for winter, though some varieties have proven themselves quite hardy in our Zone 8 climate.  The Yuzu Ichandrin, Sudachi Hybrid Yuzu, and the Flying Dragon are all cold hardy down to 0°F and can be grown outside year-round in USDA zones 8 and above.

Since our citrus are all grafted on Flying Dragon dwarfing rootstock, they do well in containers and make a great indoor houseplant.

Tips to guide you through your citrus growing journey!

1. Don’t Overwater!  Since these heat loving plants like to spend a lot of time under the sun, it can be assumed they will need to be watered frequently.  Quite the contrary is true since citrus trees are very susceptible to root rot and overwatering is one of the main causes of death in these precious plants.  For both container grown and outdoor grown citrus, we recommend deep waterings and waiting until soil dries slightly until you water next. Potting media or soils with sharp drainage are recommended to keep your tree’s root system healthy.

2. Don’t pot them up in fall or middle of winter! During fall and winter trees are not actively growing so potting them up at this time creates a wet mass of soil around their roots which can cause root rot.  Even though you might be super excited to pot your new babies up as soon as you get them, we recommend potting up in late spring or summer once active growth has commenced. 

3. Be sure to feed your citrus! While you can get away with low or infrequent fertility on some plants, citrus require a lot of nutrients to stay healthy and continue producing loads of fragrant flowers and fruit. Especially after flowering be sure to give them a good dose of citrus fertilizer to keep them lush and green.

4. Move tender varieties outdoors once all danger of frost has passed. Plants will require a hardening off period if they’ve been indoors as the light intensity is much lower. When nights are reliably above 40 degrees is typically when we move our indoor citrus outside.

5. Plant them in a well draining and acidic soil. Most potting soils are high in nitrogen and naturally acidic but adding a bit of citrus mix can help lower the pH to the 5.5-6.5 range that citrus plants prefer. We recommend planting in a regular organic potting soil and then adding 30% – 40% perlite, vermiculite or coarse bark to help with draining. If planting in ground, then it’s recommend to plant in the native soil and to amend the planting hole with an acidic mix per instructions on the box of acidic mix of choosing.

6. Spray off the leaves frequently. For almost any houseplant it’s valuable to spray off the leaves frequently so that dust does not accumulate on the leaves and it is especially important after flowering on citrus plants. That sweet nectar from the flowers drop onto the leaves and can cause a sticky mold to develop if not sprayed off a few times after flowering.

7. Keep an eye out for pests! Citrus plants are as beloved by aphids and scale as they are by us. These little sap suckers are farmed by ants that bring their eggs up from underground and place them on your precious plant. If you see ants then you likely have scale or aphids on your plant, but not to fear! There’s an easy solution. Simply take an old toothbrush and scrub them down with isopropyl or rubbing alcohol or you can make a soap spray to suffocate the little buggers. Outdoors pests are not as much of a problem but still be on the lookout for them!

8. Enjoy the harvest! Don’t forget that citrus isn’t just for fresh eating.   Thai Lime Curry, Yuzu marmalade and sake, Chinotto Sour Orange liqueur, or Pink Lemon drizzled on salmon or made into pink lemonade are just a few of the creations you can make with your homegrown citrus! 

Growing Citrus in Containers

You can grow delicious Oranges, Lemons, Limes and more almost anywhere. By growing them in pots, you can enjoy their evergreen beauty and fragrant flowers even during the coldest winter months.  Our very dwarf varieties make it easy to keep the plants small and harvest good crops of full size fruit.  While most Citrus are not hardy, growing them in containers allows you to bring your citrus plants indoors during the winter, protecting them from damaging cold temperatures.

Growing a Citrus plant in a container is not difficult.  For good growth and ultimate success, it is important to consider the following:

CONTAINERS AND SOIL

Choose a container large enough to support your plant for several years.  The larger the pot, the longer it can grow without repotting.  A 5 gal. pot is the minimum to consider for planting a one gal. size plant.  It should be adequate for 3-4 years.  A 7 or 10 gal. pot will allow more years of growth.  A 15 gal. pot or ½ whiskey barrel will likely allow 8-10 years of growth.  Consider placing a wheeled dolly under the pot to make it easy to move it indoors and out.

Once you have the container, choose a coarse, well-drained potting soil.  Propagation mix holds too much water and is not suitable.  Check the label on the bag to see if any fertilizer has been added. If not, it is a good idea to incorporate some slow release fertilizer, either chemical or organic.  Citrus plants like acidic soil so choose a fertilizer that works for Blueberries, Azaleas or other acid loving plants.

PLANTING & SITE

Partially fill your new container with potting soil, making a mound in the center high enough so the original soil surface of the plant will be a couple of inches below the rim of the pot.  Remove your plant from its existing pot and inspect the roots.  Usually it will be necessary to loosen them a bit to stop them from circling and get them growing away from the rootball.  Loosen and pull our some roots from the edge of the existing rootball and drape them evenly over the mound of soil in the new pot.  If roots are not long enough to drape them down the sides of the mound, simply rest the original rootball on top of the mound and fill the remainder of the pot, work soil around the roots and water well.

Citrus like an outdoor environment during the growing season.  You can leave your plant outdoors in late spring, summer and early fall, when there is no danger of frost.  This will keep your plant healthier and reduce the potential of pest damage.  Choose a site with at least ½ day sun.  This can be a deck, patio, or any similar place.  It should be close enough to your house or greenhouse so it is easy to move indoors in the fall.

In the fall, move your plant indoors to a location with significant light.  A south wall with windows will work.  Even better is a solarium.  If you do not have a suitable location, you can use a grow light, turned on about 16 hours a day.  

The transition from indoor to outdoor growing conditions and vice versa should be done over a period of several days.  An abrupt change of environment can cause leaf and fruit drop. 

WATERING & FERTILIZING

When you grow a plant in a pot, you are responsible for its environment.  It is important to check soil moisture often.  While your plant does not want to dry out, the biggest danger is overwatering.  During the growing season, a deep watering once a week is often enough.  In the winter, when the plant is growing slowly, if at all, a deep watering every two weeks or even less frequently should be enough.  Check the top 2-3 inches of soil to determine water needs.  When dry, it is time to water.  You can also check water by tipping the plant slightly.  You will notice the difference in weight between a fully watered plant and a dry one.  Be careful when watering dry plants as water may run off the side of the soil mass, giving the appearance of adequate water but actually leaving the root ball quite dry.  An odd but effective way to water a pot is to use ice cubes.  They will melt slowly and the water will be absorbed into the soil without runoff. 

Fertilizing can be done with liquid or dry fertilizer.  Dry fertilizer can be applied monthly during the growing season, while liquid fertilizer can applied during weekly watering.  Micro-nutrients are important, including iron, zinc and manganese.  Leaf yellowing between the veins is a sign of micronutrient deficiency.  Be sure to follow label instructions with any fertilizer you use.

POLLINATION

Most Citrus varieties are self-fertile so only one plant is needed for fruit production.  Since Citrus typically bloom in the winter, you may want to play bee and help move pollen from flower to flower.  You can do this with a small brush, with the appropriate buzzing sounds.  Citrus fruit usually ripens the winter after flowering.

PESTS

Outdoors, Citrus plants are usually not bothered by pests.  Indoors, the most common pests are aphids, spider mites, and scale.  Thankfully, dwarf Citrus are small plants and pests can be easily controlled.  Dealing with pests begins with prevention.  Before moving your plants indoors, spray them well with water to remove any unwanted guests.  When they are indoors, inspect your plants every time you water them.  Scale is dark grey or brown and looks like a little bump on stems and trunk.  Control scale by removing them with rubbing alcohol or spraying with horticultural oil at the summer rate.  Spider mites live on the undersides of leaves, and make some fine webs.  Use Safer’s Soap or a similar spray to discourage them.  Safer’s Soap and oil also work on aphids.