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Cultural requirements for pears are similar to those for apples. Pear trees on standard seedling rootstocks (like ours) are particularly“carrot-rooted,” with a good tap root but almost no “feeder” or side roots. The lack of side roots means pears often need extra watering during the first season. Sometimes our customers are a bit disgruntled when they receive a pear tree that has one long root with no side branches or root hairs. But this large tap root is a well-stocked storehouse of sugars that can provide sustained energy for the growth of the tree, and a pear tree that is watered daily should rapidly become established and make good growth. There are many pear trees over 300 years old, and their deep taproot probably plays a role in their longevity.
Pears require less pruning than apples. Their growth habit is columnar rather than spreading, allowing them to be spaced as close as 20 feet apart. (“Nova” is smaller and has a more spreading crown than our other pears.) Heavy pruning to try to shape them like an apple tree will cause massive suckering in a very upright direction. Three or four stems, each several feet long, can sprout in response to each pruning cut. To keep this response to a minimum, prune only to eliminate crossing or rubbing branches and dead wood. Summercrisp is reputed to be more “shape-able” than other pears.
Fireblight is a serious bacterial disease of pome fruits (apples, pears) and has severely limited commercial pear production in the Northeast. Most backyard growers will never experience fireblight; however, there are some fireblight-prone areas where only Ussuriensis-cross pear cultivars (Ure, John, David) with excellent fireblight resistance will survive. Fireblight is usually noticed when infected leaves, branches, flowers, and fruit suddenly turn brown, appearing as if they have been scorched by fire. Branch tips may also display the diagnostic “shepherd's crook” appearance. Closer inspection may show a clear to reddish ooze from infected tissues. A new biological control, “Serenade,” has shown promise for treatment and prevention. (See Apple Diseases.) Serious infestations may require that affected portions be cut out and burned up, including whole trees if necessary. Be sure to disinfect pruners between cuts with a 3% hydrogen peroxide or 10% Clorox solution. Streptomycin is occasionally useful against the fireblight bacterium if the infection is caught in its early stages, but should not be used in conjunction with Serenade.
As with all fruit trees, a dormant oil application in late winter is recommended to smother overwintering insects on the stem. Pears are susceptible to pear leaf blister mite and pear psylla, but a good application of dormant oil is effective against both. Occasionally the blister mite will reinfect during the summer. It causes black splotches on the leaves and raised blister-like bumps on the bark. If this happens, try one of the new summer-application horticultural oil sprays with a low volatility rating (distillation temperature) of 412 degrees F. They are light oils that will not hurt the leaves and may be used during the growing season. A foliar feed may be applied with the spray if it is May or June. Be sure not to use the regular type of dormant oil for summer spraying. Another promising control for pear psylla is the kaolin clay solution Surround, which provides a physical barrier that inhibits the pest's attraction to the leaf. For dormant oil and Surround sources, see the Source Table.