Sunday, March 16, 2008
By LEE REICH
Give your plants plenty of elbow room and they’ll reward you.
Fruits splashed all over the pages of nursery catalogs look as enticing now as they could taste in summer, so long as you don’t bite off more than you can chew.
When planning what fruits to grow, make sure every plant has enough elbow room.
A strawberry plant needs its one square foot of space and a full-size apple tree needs its 500 square feet.
That space is needed to let every leaf bask in sun and bathe in breezes and so nourish plentiful and tasty fruits.
Just how far apart to set plants depends, of course, on how big they’ll grow.
The richness of your soil and your fertilizing, pruning, and watering all play a role.
But the main determinant how big a plant will grow is its inherent, or natural, vigor.
APPLES FAR FROM THE TREE
With some kinds of fruits, you can choose the inherent vigor of the plant you want, from dwarf to full size.
A particular variety of fruit might grow on a naturally dwarf plant or it may be made dwarf by being grafted onto a special dwarfing rootstock.
Northblue, for example, is variety of blueberry that is naturally small, never growing more than a couple of feet high, while Bluecrop, another blueberry variety, is naturally larger, the bushes easily reaching 6 feet, or more, high.
Another example: A single variety of apple, such as McIntosh, might be borne on a full-size, 25-foot-high tree if grafted on one rootstock, a 15 foot tree if grafted on a semi-dwarfing rootstock, or only a 6-foot-high tree if grafted on a dwarfing rootstock. In this case, it is the rootstock, not McIntosh’s genetics, that determines eventual size.
McIntosh fruits will taste identical from any of these trees. But the Northblue fruits are different from the Bluecrop fruits.
BIGGER IS NOT ALWAYS BETTER
With fruit trees, an advantage of dwarf over full-size is that they are easier to care for.
You can do most or all your pruning, harvesting and other work with both feet on terra firma.
Smaller plants are also just the ticket for smaller yards.
And whatever the size of your backyard, you can cram in more small plants than large plants. So instead of six bushels of fruit from one large McIntosh tree, you could harvest a couple of bushels each of Spigold, Mutsu, Gravenstein, and Macoun apples from four dwarf trees occupying the same space as that single large tree.
Not only do you get more variety in apples, but, because small trees use sunlight more efficiently than large trees, you actually harvest more total apples.
Or, you could expand your palette and your harvest season by planting a couple of dwarf apples, dwarf peaches, and dwarf plums in that same space.
Still, one full-size tree better suit your needs if you enjoy cooking up and canning a big batch of applesauce all at once.
Generally, large trees also tolerate drought, poor fertility and other adverse soil conditions better than dwarf trees.
With age, a large tree develops a majestic quality and provides shade and limbs for climbing.
And besides, for some kinds of fruits, you have no choice.
AND THE NUMBERS ARE ...
Space large fruit trees at least 20 feet apart, medium-sized trees 15 feet apart, and small ones 8 feet apart.
If you plant more than a row of trees, allow more spacing between rows.
Only half these distances are needed for planting adjacent to a wall or fence.
Give bush fruits 6-foot spacing, except for strawberries and red raspberries, which need 1- and 2-foot spacing, respectively.
Blueberries and currants make attractive, edible hedges, in which case you could set plants as close as 4 feet apart to let them form a continuous row of plants. Consider lining a walkway with such a hedge, and you can graze as you walk.