Plums

Plum orchards once covered The Valley of Heart's Delight (what is now known as Silicon Valley). Many homes are still graced by individual specimens of these prolific fruit producers, and it is easy to add one to your landscape, as well.

​Plums are members of the Rose family, in the Prunus genus. This makes them cousins to other stone fruits, such as peaches, nectarines, and cherries. One variety of apricot (Prunus armeniaca) is so closely related that it is actually a plum! Fruits of the plum tree are called drupes.

Purple plums (Pikist)

Plum varieties

When deciding on a plum variety, keep in mind that plums can be sweet or tart, early or late blooming and ripening, standard size, dwarf, or semi-dwarf. Two varieties are commonly grown are Japanese plum (Prunus salicina) and European plum (Prunus domestica), but there are others. Some European plum varieties do not require cross-pollination, but all plum trees produce far more if there is a second tree nearby. Japanese plums bloom and mature earlier, but European plums tend to be sweeter.

Purple plums (Wallpaper Flare)

​Standard plum trees can grow to 30 feet tall and 25 feet wide, semi-dwarfs can be 15 feet wide, and dwarf varieties rarely need more than 10 feet. Plums come in skins of many different colors, from yellow, to red and purple, to nearly black. The interior fruit can be yellow, white, red, or green. Commercially, plums grown to be consumed as fresh fruit are called “sugar plums”, while the remainder are grown to be dried and sold as prunes. Prunes are almost exclusively made from European plums. You can also find plum-apricot and plum-cherry hybrids!

Red plums (Couleur)

How to grow plums

Plums love mild winters and hot, dry summers. While they prefer more sandy soil than many gardens tend to have, they are pretty tolerant of clay, as long as the drainage is good. They do need a lot of sun. Plums are best started from certified disease-free root stock. You can also start a tree from a friend or neighbor’s tree by taking one of the many suckers that tend to appear. Suckers root more easily if they are dipped in rooting hormones (auxins), but they will create their own auxins in a day or so. If starting from seed, plums should be planted 3 inches deep. Be sure to mark the spot so you don’t lose track of your new baby!


Plum tree care

Plum trees thrive here in warm regions. Trees do require the following seasonal care:

• Winter - prune into an open center shape, removing dead and/or diseased limbs and 20% of the previous year’s new growth; spray with dormant oil
• Spring - treat with fungicide, such as fixed copper; feed mature trees 1-2 lbs. of urea or 20-40 lbs. of manure, and young trees (April - July) with 4-8 oz. urea or 10-20 lbs. manure; water deeply every 2-3 weeks; thin fruits to 4-6” apart; check for aphids
• Summer - continue feeding young trees; keep weeds and grass at least 3 feet away from trunks using mulch; water deeply every 2-3 weeks
• Fall - harvest; remove all mummies and fallen fruit; feed and water after harvest; after leaves fall and just before heavy rains, treat with fixed copper

Plum tree pests & diseases

The most common plum pests are aphids, mites, and San Jose scale. Other pests include Oriental fruit fly, plum curculio, mealybugs, redhumped caterpillars, green fruit beetles (Cotinis mutabilis), and mealy plum aphid (Hyalopterus pruni). Sticky barriers can reduce the impact of many crawling insect pests. Fungal diseases that affected plum trees include canker, brown rot (Monomania fructicola), and shot hole, also known as Coryneum blight.


One of the most common problems faced by plum tree owners is overproduction. Overproduction, or overbearing, can cause broken limbs, so it is important to thin fruit to no more than one fruit every 2 to 4 inches. Don’t be concerned if your plums have a whitish coating on them. This is a protective epicuticular wax known as “wax bloom” and is easy wiped off.


​Add a plum tree to your landscape this spring for decades of delicious summer fruit and year-round jams and jellies!