Exotické rostliny, Zdeněk Černoch, Větřkovice u Vítkova

Anona - Anonaceae
Anona is an extensive genus from the Annonaceae family originates in South or Central America. There are more than 100 different types and varieties of Anona growing wildly in the tropical rainforests of America, Asia and Africa. Most of these plants are also grown for food, expensive wood and alkaloids.

Anonas are evergreen or deciduous, not very tall trees and shrubs with a low crown and entire leaves. They usually have plain flowers that grow individually from the leaf axils. Corolla is usually made of 6 petals; 3 outer (larger, leathery, deep green) and 3 inner (thin, pale or yellow) petals. Each flower has many stamens and carpels. After the successful pollination a new, carnose, juicy follicle with one seed is formed from each carpel and it grows together with other follicles and becomes a collective fruit (similar to bog strawberry). The pulp contains lots of flat, egg-shaped, brown or black seeds.

Annona cherimola
Annona cherimola is a small tree or a bigger shrub that can grow up to 5-9 meters. A leaf cast usually comes before the spring shooting. The leaves of Annona cherimola are oval, 7-15cm long and 4-9cm wide. Its small discreet flowers grow either individually or in clusters of 2 or 3 on short peduncles along the branches. Each flower consists of 3 bigger, green, fleshy, 3cm long outer petals and 3 smaller inner petals. There are just as many stamens as carpels. After the successful pollination a new, carnose, juicy follicle with one seed is formed from each carpel and it grows together with other follicles and becomes a collective fruit (similar to bog strawberry). Most of the fruit can weigh from 150 to 500 grams, but it’s not rare that some fruit can weigh 2,5kg and more. It is very soft in full ripeness and the juicy pulp has excellent aroma and delicious flavor. It contains several seeds similar to beans.
Varieties: Whaley, Deliciosa, Midseason, McPherson, Ryerson, Chaffey, Horton, Loma, Sallmon and other…

Pollination: The problem with pollination of Annona trees is that stamens and carpels usually mature at different flowering phase and therefore pollination by hand is necessary. Flowers must be pollinated within 6-8 hours, while the carpels are still sticky. Pollen is collected during the night and kept in a jar overnight. In the morning it is possible to pollinate the carpels by hand. Only few flowers are pollinated simultaneously and the fruit gained from pollination by hand is bigger and tastier.

Climate: Annona is a subtropical tree or shrub that requires at least 4 months of rest during the winter. Winter temperatures should range from 5-15°C and this plant doesn’t like tropical lowlands. Ideal temperatures for healthy growth are 18 - 25°C, but Annona tolerates also light frost down to -3°C during the winter vegetation rest.
This tree also prospers in areas with annual drought and annual precipitation 1000mm. Optimal soils are rich in humus, nutrients and have pH 6,5 -7,6. To achieve the best yields and healthy growth you can also use fertilizers.

It is possible to grow Annona in our climate just like citruses. It is necessary to let it grow outside during the spring, summer and autumn. The plants shouldn’t be exposed to temperatures lower than 10°C in our climate in autumn and should be recovered inside. Another option would be to cultivate Annona in subtropical greenhouse along with other plants and citruses in the soil. These conditions are however so favorable that the plant will soon outgrow any greenhouse. If you succeed in pollinating Annona trees, they will reward you with an extremely delicious fruit.