You can’t judge a book by its cover, so a photo of the fruit is the worst reason to select a fruit tree. All over America folks will spend the spring bare root season picking out their trees based on staged photos of luscious, ripe fruit on labels and catalogs. Years down the road when a tree fails to fruit, it’s a huge disappointment – and most never learn why theirs refused to bear.
What the majority of novice gardeners never learn are the five factors that determine whether that tree will produce fruit in their backyard. These invisible characteristics are vital to the selection process, and they pay off in big harvests later on.
1 Chilling hours: Fruit trees require a certain number of hours at low temperatures in wintertime. Plums require the least chilling at 400 to 750 hours. Cherries require the most chilling at 1,000 hours or more. Try to grow cherries in a milder winter climate and they will gradually decline in vigor from lack of dormancy.
2 Late frost: Many fruit varieties are “early” bloomers. Novices often select them thinking they’ll get fruit earlier in the season. In many areas where late frosts and rain occur in springtime, early flowers often go unpollinated. When it’s freezing and wet, bees don’t fly, so flowers don’t get pollinated. These conditions can also damage the tiny reproductive parts of the flower so even if bees do visit, pollination fails. Therefore, it’s much safer to purchase varieties that are designated midseason or, better yet, late season to guarantee that your efforts pay off.
3 Regional diseases: Each region experiences its own set of diseases that afflict fruit trees. Spraying a tree is not so easy for novice gardeners, and it’s undesirable among organic gardeners. Therefore, do your homework to find out what fruit trees are afflicted with disease in your area and either avoid them or seek varieties designated as resistant.
4 Pollinator? Some kinds of fruit require a specific pollen source. Certain apple trees require an apple of a different variety nearby for cross-pollination. Without the second tree, little or no fruit is produced. Those two varieties must bloom on the same schedule to achieve cross-pollination success. If you are only planting a single tree, choose varieties designated self-fertile.
5 Size: Fruit trees are typically grafted onto a disease-resistant, vigorous rootstock. The graft union is visible at the base of the trunk. Rootstock can influence the size of the mature fruit tree by dwarfing it to simplify maintenance and to allow the trees to grow in smaller spaces. A single variety such as Bartlett pears is grafted to produce mature trees in three different sizes: standard, semi-dwarf and dwarf. Semi-dwarf is ideal for the average yard, dwarf trees are better for the city, and standard trees are chosen in deer country to limit browsing.
To help you better understand the five factors in greater detail, with handy references to specific varieties, go to RaintreeNursery.com. Click on “Growing Info,” which takes you to an excellent archive of detailed articles. Here you’ll find a helpful chilling hours chart and a pollination guide. They’ve also broken down varieties into regions to help you go right to those that are reliable in your area. So when their varietal photos and descriptions sound appealing, double check the five factors first, and only then place your order.
McClatchy-Tribune News Service
Maureen Gilmer is an author, horticulturist and landscape designer. Contact her at mogilmeryahoo.com.