The Cherry of the Rio Grande, Eugenia aggregata, is a native of Brazil and grows quite well in South East Queensland, George has one in his backyard that is 5m high. It is a small evergreen tree, 4-5 meters in height, with dark green, glossy, waxy leaves very similar in appearance to other eugenia species such as brazilian cherry (E. uniflora) and grumichama (E. brasiliensis).
The flowering season starts in spring and extends over three months, like the grumichama it has a few crops per year. The flowers are white and quite showy. The one-inch oblong fruit is a beautiful dark red to purple, and is produced soon (~3weeks) after flowering. The fruit is thin skinned with one large seed in the centre. The fully ripe fruit is generally tarter than the grumichama and has a very juicy flesh. It is considered by our president to be superior in quality to the grumichama.
The fruiting season usually is September – December. The fruit is nice fresh and can be used in jellies, jams or juices. The fruits also freeze well, so they can be picked when mature and frozen for later use.
Cherry of the Rio Grande is still usually propagated by seed, although seedlings may take up to 4 to 5 years to begin producing fruit. If superior varieties, for example, large-fruited forms or sweeter fruiting forms, are found by anyone growing a number of plants, they be propagated by grafting onto seedling rootstocks. Veneer grafting has been successful but other variations could also work. Considered a slow grower, cherry of the Rio Grande will grow at the rate of 2 to 3 feet per year and makes a very attractive large shrub or small tree, depending on how it’s trained.
Most Cherry of the Rio Grande grow on a wide variety of well drained soil types; however, they prefer a slightly acid soil, and on alkaline soils may develop some micronutrient deficiencies.
Most of the time there is little problem in SEQ from cold, since cherry of the Rio Grande can tolerate temperatures down to –3 to -4° C without being killed. Trees should be fertilised with a fruit-tree-type fertiliser at least three times a year for good growth and fruiting. During periods of dry weather they will benefit from weekly irrigation.
Birds find the fruit tempting and the upper parts of trees are often picked clean before the fruit is even fully mature, it is also susceptible to fruit fly damage.
Cherries of the Rio Grande are easy to grow, requiring relatively little maintenance for the growth of healthy, productive plants. Fruit size and quality depends to a large extent on proper nourishment and an adequate water supply at the time of fruit development. When first planted, they need a complete fertiliser in a 1-1-1 ratio, that also contains magnesium. Start with no more than 100g at monthly or bi-monthly intervals, increasing the rates commensurate with growth.
If iron deficiency in calcareous soils is a problem, this should be applied in a chelated form by drenching into the soil when needed. Nutritional sprays to supply other minor elements should also be applied as needed. They should always be supplied with adequate water especially during bloom and fruit development. Cherry of the Rio Grande has fairly good drought tolerance. It requires little pruning to make an attractive tree and is sometimes pruned to make a hedge.