Growing apples is highly rewarding, but don’t try starting one from seed.
Apples (Malus pumila, aka Malus domestica) have a rich and varied history. They hold a place in nearly every culture and religion, being one of humankind’s earliest attempt at tree cultivation. Wild apple trees (Malus sieversii), however, bear little resemblance to their domesticated progeny. Wild apple trees, still found in central Asia, can grow up 40 feet in height and the fruit is smaller and more tart than most people find palatable. Most of the apples you see in the grocery store are crosses between Malus pumila and crab apples. To date, there are over 7,500 apple cultivars with various traits of skin color, texture, disease and pest resistance, juiciness, storage ability, and more. In 2010, the entire apple genome was mapped, with over 57,000 genes identified. (Humans are estimated to have up to 25,000 genes - kind of makes you wonder, doesn’t it?)
Bare root apples
The best way to start growing apples is with bare root stock. When selecting your root stock, keep in mind that some apple varieties require cross-pollination, while others are self-pollinating. If you only have room for one tree, you will want to be sure to select a self-pollinating variety or all you will get is summer shade. Bare root stock should be planted in January, February, or March in the Bay Area. According to UC Division of Agricultural and Natural Resources (UCANR) and local Master Gardener trials, and depending on your tastes and microclimate, there are many apple varieties that perform well in Santa Clara Valley. Before you buy, however, you may want to conduct a soil test with a reputable lab. This is an excellent investment in a tree that will probably live and produce fruit for the next 100 years or so. Also, consider the size of your mature tree - it is far easier to pick apples and care for your tree if it is a dwarf or semi-dwarf variety.
Most red varieties will need more chilling hours than they will get in California's Bay Area. Red apples generally need 1200 to 1500 chill hours to fully develop their color and flavor, while some microclimates in San Jose only receive 400 chill hours a year, on average. Also, our local fog can cause more russetting. Russeting is when the apple’s skin turns brown and rough.
How to grow apples
Apples grow best in well-drained, nutrient rich soil with full sunlight. Apple trees need some space for good air flow. Full-sized trees will need a 15 to 20-foot circle of space, while dwarf varieties need only 10. Dwarf apple trees do tend to over-produce, breaking branches, so you may need to do more pruning or provide supports. Once your bare root tree arrives, dig a hole that is twice the diameter of the spread out roots and as deep as the root ball. Failing to plant trees at the proper depth causes more tree deaths than any other. You should remove any grass or weeds that are growing within two feet of this circle. Remove any dead, damaged, or diseased roots and then soak the root stock in a bucket of water for a couple of hours (overnight, if the roots are really dried out). Mix some aged compost in with soil from the hole and spread it out in the bottom of the hole. Be sure to not leave smooth edges in the hole. Our heavy clay can create an impenetrable barrier to young roots. You can help your apple tree get a better start by roughing up and scoring the edges of the planting hole. Place the tree in the hole, making sure that the graft union (the place where the root stock joined the scion) is at least 2 inches above soil level, to avoid crown rot and other fungal diseases. Resist the urge to press the soil down to eliminate big air pockets and mud in the tree instead, giving it a good drink of water. You can also grow dwarf apple trees in containers!
Seasonal apple care
Apple pests and diseases
There are very few pests or diseases that will actually kill an apple tree, but it has many attackers. The use of sticky barriers around the trunk will halt some, such as ants, slugs and snails, and Fuller rose beetles, but most apple problems are carried on the wind. Stem blight, crown gall, leaf spot, powdery mildew, fireblight, and other bacterial blights are common diseases. Cedar apple rust can also occur if apples are grown near Eastern red cedar trees. Also, apples share a susceptibility to bacteria blast with lilacs and stone fruits. Common pests include codling moths, apple maggots, San Jose scale, redhumped caterpillars, armyworms, and Eriophyid mites. New to the apple scene is another pest, chili thrips.
Find a spot in your landscape for one of these beauties, because plucking an apple from your very own tree and taking a bite, well, it's just one of life's finer experiences. And we all want to keep that doctor away!
You can grow a surprising amount of food in your own yard. Ask me how!