(News article for September 16, 2023; edited)
I’ve covered several different types of fruit crops in past articles. I tend to write about ones – such as blueberries, figs, persimmons, muscadines, and blackberries – that are relatively easy to grow with good site selection and preparation, appropriate variety selection, and adequate care.
Today, however, I’m addressing plums. These are not the lowest maintenance of fruit crops. In fact, they tend to produce less reliably than peaches in Louisiana.
Cultivated plums are largely of two types: Japanese (Prunus salicina) and European (primarily Prunus domestica). (I grew up calling loquats “Japanese plums,” but that’s not what I’m talking about here.) The kind that we see in the produce sections of grocery stores are generally Japanese plums. European plums are typically oval-shaped. Some are eaten fresh, and others are dried for prunes.
Plums have many of the same disease and insect problems that peaches have, which is to say a lot. Examples include peachtree borer, plum curculio, and brown rot. They are also susceptible to an additional disease, black knot. Growing plums in Louisiana isn’t for those who want reliable, long-term production with little effort.
Most plums need to be cross-pollinated by another variety, so planting two varieties is recommended. Methley is an exception. It’s considered self-fertile.
As with many fruit crops, chill hours are important when choosing a plum variety. If a variety requires too many chill hours for your location, it won’t flower and fruit consistently and may eventually die. If it requires too few chill hours, it’s likely to bloom too early and have flowers or small fruits killed by late freezes.
Besides the self-fertile Methley, Bruce and Byrongold are suggested for the Florida Parishes area of Louisiana. Methley has red to purple fruit when ripe. The skin of Bruce turns red when fully ripe, but it’s often harvested as a “green plum.” The fruit quality is not great, but it’s one of the more reliable producers. Byrongold has yellow skin and flesh.
As for most fruit trees, it’s important to choose a site with good drainage and full sun exposure when planting plum trees. Soil pH should be between approximately pH 6 and 7.
Plum trees are often trained in the open center or vase form, like peaches. This starts with cutting the tree off at about 24 to 36 inches while the tree is dormant and then choosing three to four outward-growing scaffold branches during the first growing season.
Louisiana has several native plum species that provide food for wildlife and, occasionally, for humans. They also support pollinators. Chickasaw plum (Prunus angustifolia) seems to be the most popular native plum for fresh eating. It’s also the one I’ve seen offered for sale from the most places. (The bar is pretty low. None of these are widely sold.) Other plums native to Louisiana’s Florida Parishes include Mexican plum (Prunus mexicana; this one has the largest fruit among the native plums), American plum (Prunus americana), and hog plum (Prunus umbellata). The US Geological Survey’s Plants of Louisiana website has information about and photos of each of these species.
If you’re interested in planting fruit plants this winter and want to be able to choose varieties that are not commonly sold locally, you may want to go ahead and look into reserving or ordering the varieties you want. Make sure that, if plants will be shipped bareroot, they won’t be shipped till the dormant season.
Let me know if you have questions.
Contact Mary Helen Ferguson.
Methley plum trees are unusual among cultivated plum varieties in that they are self-fertile. (Photo: Ketzirah Lesser & Art Drauglis, CC-BY-SA 2.0)
Unripe Chickasaw plums (Photo: Larry Allain, US Geological Survey)
Mexican plums (Photo: Kelby Ouchley, Bayou-Diversity)