Culture
Best grown in deep, loamy, moderately fertile, slightly acidic, medium moisture, well-drained soils in full sun. Tolerates average garden soils, but unamended heavy clay soils which waterlog easily and drain poorly should be avoided. Generally, the more dwarfing the rootstock, the greater the need for soil fertility. Needs full sun for maximum flower and fruit production. More than one variety must be planted in order to facilitate best pollination and subsequent fruit production. For basic cultural information on the growing of apples, see Home Fruit Production, Apples (University of Missouri Extension publication G6021), which is available for inspection or purchase at the Kemper Center Information Desk.
Stark Bro's Nursery of Louisiana, Missouri recommends Malus 'Enterprise' and Malus 'September Wonder Fugi' as good cross pollinators for Malus 'Sweet Sixteen.'
Noteworthy Characteristics
Malus is a genus of about 35 species of deciduous trees and shrubs from Europe, Asia and North America. Some eating apples are hybrids but others are attributed to M. domestica or M. pumila.
Edible apple cultivars do not grow particularly well on their own roots. As a result, apple varieties sold in commerce today have all been grafted onto rootstocks which, inter alia, control the size of the tree. Rootstocks are generally classified as follows (tree height in parenthesis): dwarf (8-10'), semi-dwarf (12-15') and standard (18-25' or more). All trees bear full-size fruit, however. Most trees sold today for the home apple grower are grafted onto dwarfing rootstocks (dwarf or semi-dwarf), resulting in trees which, in comparison to standard trees, are (1) easier to manage (spray, prune and harvest) and (2) produce fruit at an earlier age.
Genus name from Latin is an ancient name for apple.
‘Sweet Sixteen’ is available in commerce today on both dwarf and semi-dwarf rootstocks. Ripe apples of this cultivar are generally characterized as being rosy red, juicy, crisp and sweet. 'Sweet Sixteen' is recommended for use as a dessert apple, fresh eating apple, juice apple, cooking/baking apple and for canning or freezing. White blossoms bloom in early spring, followed by apples that ripen in late September in the St. Louis area. 'Sweet Sixteen' is a cross between M. 'Malinda' and M. 'Northern Spy'. It was introduced by the University of Minnesota in 1977, and has good winter hardiness.
Problems
‘Sweet Sixteen’ is noted for having resistance to apple scab and fireblight. It has some susceptibility to cedar apple rust and powdery mildew. Potential insect pests include aphids, maggots, codling moth and plum curculio. Spider mites can also be a problem. Regardless of disease resistance levels, good cultural practices are always essential and some chemical spraying may become necessary in order to control pests.
Uses
‘Sweet Sixteen’ is pruned and grown primarily with a view toward producing quality fruit, and its ornamental features are usually considered secondary. It should be grouped in a sunny location with other apple varieties. Spring apple blossoms and fall fruit do, of course, add color and interest to the landscape.