Au Rosa Plum Tree

Growing fruit in the southeast is not always easy. The heat and humidity mean that diseases are often widespread, that wouldn’t be seen in other areas. Always keen to develop new crops for farmers, plant breeders can give gardeners a bonus too, and that is certainly true with the Au Rosa Plum Tree. It was bred at Auburn University in Alabama as an improved version of the traditional Santa Rosa plum. That variety grows well in the west, but not in the southeast. Those breeders succeeded, and created a form of Santa Rosa that is almost totally disease resistant and reliable, producing great crops of big, tasty, red plums. It doesn’t need a second tree for pollination, and that’s a big bonus for home gardeners too. They also don’t want to be spraying and fighting diseases, so if you live in zone 7 and cooler parts of zone 8, this is a plum for you. Given its parentage it will also grow right into zone 5, making this a great all-round plum for everyone who wants to enjoy natural, organic crops, free of harmful chemicals. And of course, for everyone who enjoys a really tasty plum.

Growing the Au Rosa Plum Tree

Size and Appearance

The Au Rosa Plum Tree is a deciduous flowering tree that grows rapidly to around 15 feet tall and 10 feet wide. It forms an upright tree with dark green leaves, and begins cropping at an early age. It has white flowers around the end of March, and these develop into baby plums easily, with no need for another variety of plum for pollination. Cropping is heavy, and within 4 years it could be producing 50 pounds of plums, with older trees soon giving 100 pounds. The plums are over 2 inches across, with a dark red skin and yellow flesh. This is a clingstone variety, with sweet, delicious flesh with a great flavor and lovely texture. The plums ripen in late June, and you can look forward to reliable annual crops when you plant this carefully bred variety. Unlike most older varieties, this plum stores relatively well, keeping for 6 weeks in the fridge almost perfectly, and still acceptable after 9 weeks. Eat it fresh, stew it for desserts, bake it into cakes or turn it into preserves and jams – this is a wonderful and easy fruit that you will love having available from your garden.

Using the Au Rosa Plum Tree in Your Garden

Because it doesn’t need a second variety, and because it is tough and disease resistant, the Au Rosa Plum Tree is ideal for smaller gardens, and for growing among your flowers and bushes. Plant it on a lawn, or at the back of a flower bed to enjoy the spring blooms. Grow it along a fence or as a screen, perhaps mixed with other fruit trees as a home orchard.

Hardiness

The Au Rosa Plum Tree needs 700 chilling hours each winter, with temperatures below 45 degrees. This means it is reliable in zone 7 and in northern parts of zone 8 with cooler winters. It has not been widely tested in cold regions, but there doesn’t seem any reason, given its relationship to the Santa Rosa Plum, that it wouldn’t be reliable and hardy at least in zone 5.

Sun Exposure and Soil Conditions

Grow this tree in full sun for the best and biggest crops. It will grow in most ordinary soils that are well-drained, and it is much less particular about soil than many other fruit trees. Alkaline soils are fine, and really, anywhere that isn’t constantly wet and soggy.

Maintenance and Pruning

Specifically bred and selected for disease resistance, the Au Rosa Plum Tree is remarkable. In trials it proved to be completely free of all important plum diseases including (wait for it. . .): bacterial fruit spot; bacterial leaf spot; bacterial canker; black knot; brown rot; and plum leaf scald. It was the only variety to have zero presence of all these diseases in a trial that included all the important plum varieties.

History and Origin of the Au Rosa Plum Tree

The Japanese plum, Prunus salicina, actually originated in China, but the first plants in America came from Japan. They were brought over by that America genius of fruit breeding, Luther Burbank, in the later decades of the 19th century. Since then it has been used to create the many varieties that are used for most commercial plum growing. Burbank used it along with other species, probably Prunus simonii, the apricot plum from China, and the wild American plum, Prunus americana, to make many hybrids. The most outstanding is the variety called ‘Santa Rosa’, widely grown, but not very disease resistant. In the 1980s Dr. J. D. Norton and his team of breeders and researchers at the Alabama Agricultural Experiment Station, part of Auburn University, started plum breeding. They produced a range of varieties all with ‘AU’ in their names. Perhaps the most outstanding is ‘AU-Rosa’, which has as parents the Santa Rosa Plum and a variety of the Chickasaw plum, Prunus angustifolia. That plant grows wild across most of southeastern and central America, down into Florida and across to Texas, and was eaten by native Americans. The variety you used was an experimental one called ‘Starcher No.1’. After several generations of breeding they had what they wanted – the tree we call Au Rosa Plum.

Buying the Au Rosa Plum Tree at the Tree Center

We are totally amazed at how good this plum is, and how disease resistant. The trees have a good productive life, and make a great addition to your garden. Everyone is searching for these Auburn University plums, they are getting such good reviews, and the Au Rosa Plum is the top variety. We were lucky to find these plants, and if you act quickly, and order right away, you can be lucky too. But don’t wait, or they will all be gone.