Editor’s Note: Thank you to Editor James Fowler from Yolo County Master Gardeners (UCCE) for agreeing to share this article. Michael Kluk is both a master gardener and a writer for Cool Davis. See his bio at the end of this article.

In the Winter 2020 edition of the Yolo Gardener, we described general citrus care. At the time, we realized that growing citrus in containers warranted its own article. So now we can delve more deeply into that topic. Look back at the Winter edition article for general care suggestions.

Of all the fruit trees, citrus is the easiest to grow in containers with the possible exception of figs. Many varieties of citrus adapt well to container culture and, in fact, may do better than when planted in the soil. They will be smaller but often still large enough to give you a healthy amount of fruit along with beautiful glossy leaves and wonderful smelling blossoms.

Choose the right varieties

Not all varieties of citrus will do equally well in a container. A fullsize grapefruit tree may not be the best choice. The varieties most likely to be happy in a container are those that tend to be smaller in size when mature. Here are a few suggestions:

  • Mandarins-Satsuma, Clementine, or Honey
  • Lemons-Improved Meyer, Sungold, Variegated Pink, or Ponderosa
  • Limes-Bearss, Thornless Mexican Lime, Palestine Sweet Lime, or Mausambi
  • Kumquats-Fukushu, Meiwa, or Tavares Limequat (a cross between a kumquat and a lime)
  • Oranges-Washington (a naval orange), Tarocco (a blood orange), or Trovita (a non-naval with thinner skin)
  • Kaffir Lime-the leaves are used in Thai cooking
  • Buddha’s Hand Citron-unique fruit for zesting

Choose the right container

Choose a container a little bigger than the container your tree comes in from the nursery. Eventually you will want to move up to an even larger container but not initially because it is hard to control the water in a pot that is too big. Bad container choices include unglazed ceramic, black, or metal pots. Citrus like consistent moisture. Unglazed ceramic makes it harder to maintain moisture. The roots prefer to be cool; black or metal pots tend to heat up more. Light colored plastic is a good choice as is glazed ceramic and wood containers. In any case, start by drilling extra holes in the bottom to promote good drainage; at least three or four half-inch diameter holes is a good start. You may need to place fiberglass window screening over the holes to keep the potting soil from running out. And it is a good idea to put the pot up on bricks so that water drains out freely and the pot does not sit in a puddle. As the tree grows, you will need to move it to a larger pot. Plan on doing that every three years or so. Eventually, your tree should be in a pot that is twenty-four to twenty-eight inches in diameter. A half whiskey barrel or half poly barrel can be good options.

Choose the right soil

Citrus prefers acidic soil (pH 5.8-6.5) that drains well. Garden soil is too heavy. Many potting soils are neutral pH and also will compact too much. Start with an acid planting mix but then add twenty-five percent pathway bark or perlite. If you start with a regular planting mix, combine it with equal parts of peat, sand and perlite or pathway bark. Do not use a potting soil that has a chemical wetting agent to help it retain water. Do not add gravel to the bottom of the container, this will not aid drainage.

Planting and transplanting

When planting the tree out of the nursery pot, make sure it sits at the same level in the new container as it did in the old or possibly a little higher. It is often a good idea to gently firm up the soil in the bottom before placing the tree to minimize the chance it will settle. Leave a couple of inches between the soil level and the top of the container so that you can easily water the tree. Avoid disturbing the roots when planting and transplanting as much as you can. Do not intentionally spread the roots or break up the root ball unless the tree has become badly rootbound. In that case, gently spread two or three roots so that they are pointed out into new soil. Prune off any roots that seem broken or otherwise damaged.

Location, location, location

One of the benefits of growing citrus in a container is that it can give you a better selection of locations for your tree. Select a spot that will get at least eight hours of sun, more if possible. Ideally, place your citrus in a location that will get morning sun but some shade on a summer afternoon. The morning sun will help to dry the leaves, limiting fungal diseases. In the winter, it will help to warm the tree earlier and reduce the likelihood of frost damage. Afternoon shade will help maintain soil moisture in the summer. A full day of sun is ideal in the winter, however. One benefit of growing citrus in a container is that you may be able to offer it different summer and winter abodes, the best of both worlds. Generally, citrus can be left outside here through most winter nights. However, if the temperature is predicted to fall below 37 deg. F, which can allow frost to form, moving your plant into a protected area or even inside is preferrable. Some people put their container grown citrus on a wheeled dolly. Otherwise, a hand truck is a useful tool.

Water and fertilizer

Citrus grown in containers will require more frequent watering than those grown in the ground. Citrus soil should stay evenly moist although not soggy. You may need to water every other day in the heat of the summer but be sure to check the soil moisture a few inches down to judge. A layer of mulch such as dried leaves or straw Spring 2021 YOLO GARDENER 10 is a good idea in your container tree as well as the rest of your yard. Keep the mulch a few inches from the trunk of the tree. A plant fertilizer for acid loving plants, such as azaleas and camelias, seems to work best for citrus in containers. Apply as directed on the container.

Growing citrus in containers can be rewarding. For some, with small yards or consistent shade in most parts of the yard, it can present the best option for enjoying the year-round foliage, fragrant blossoms and delicious fruit that citrus provides.

References

https://www.fourwindsgrowers.com/pages/growing-dwarf-citrus

https://www.gardeners.com/how-to/citrus-in-planters/7933.html

https://www.kellogggarden.com/blog/gardening/tips-for-growing-citrus-trees-in-pots/

https://cals.arizona.edu/yavapai/anr/hort/byg/archive/growingcitrusincontainers.html

https://balconygardenweb.com/citrus-trees-for-containers-growing-citrus-in-pots/

Visit the Yolo County Master Gardener webisite

http://yolomg.ucanr.edu/Yolo_Gardener/

Read the full Spring newsletter

http://yolomg.ucanr.edu/newsletters/Yolo_Gardener88995.pdf

Full list of this spring’s articles:

“The Gardening-Nurturing Connection” – Sharon Schwarz

“Building a Community Treasure: How UCCE Master Gardeners Helped Create an All-Volunteer Public Garden” – Ann Daniel and Peg Smith

“Doggone It! Common Landscape Plants Toxic to Dogs” – Michelle Haunold Lorenz

“It’s Easy to Grow Citrus in Containers” – Michael Kluk

“Invite Songbirds to Your Yard with Native Plants” – Tanya Kucak

“Change in Leadership at Grace Garden” – Cid Barcellos

“Adapt Your Garden to Climate Change” – Deborah Sorrill

“Passalong Plants” – Sue Fitz

“Spring Garden Tips 2021’ – Peg Smith

“UCCE Master Gardener, Yolo County, Plant Sale”