Barbara J. Bromley, Mercer Co. Horticulturist 2004

None of the following is cast in bronze, but these "rules-of-thumb" do apply in most circumstances (or often enough to be reasonable) in the home garden and landscape in central New Jersey, USDA hardiness zone 6-7.

LAWNS

• Mother’s Day (to Memorial Day), Labor Day, and Thanksgiving are the best times for sunny lawn fertilization. Mother’s Day (to Memorial Day) and Labor Day are the best times for shade lawn fertilization.
• If your lawn is fertilized only one time each year, Labor Day is the best time.
• Zoysia lawns are fertilized only between mid-May and August in New Jersey.
• Labor Day got its name because that’s when you work on your lawn. (This includes renovation, seeding, aerating, dethatching, fertilization, liming.)
• During the growing season mow residential cool season grass lawns no shorter than 2 ½" to 3". Mow zoysia lawns no taller than 1 ½".
• Do not remove more than 1/3 of the grass blade at each mowing.
• Preemergence crabgrass controls are usually applied in mid-April when forsythia is in full bloom.
• Leaving grass clippings on the lawn does not promote thatch.
• Fertilizer applications may be reduced by 25% to 50% if clippings are returned to the lawn.

VEGETABLE AND FLOWER GARDENS

• To reduce spread of diseases, do not touch vegetable garden plants (especially beans and tomatoes) when they are wet from dew, irrigation, or rainfall.
• The times to pinch many chrysanthemums are Mother’s Day, Father’s Day and the 4^th of July.
• Do not plant most annual flowers and warm season vegetable plants before Mother’s Day.
• A flowerbed should be no wider than can be accessed from both sides (for weeding, cutting, deadheading, or other maintenance chores) or from a path without stepping in the garden.
• Plant lima beans on June 1.
• Plant corn when oak leaves are the size of mouse ears (dime-sized).

PESTS AND THEIR CONTROL

• Use pesticides as you should use antibiotics… only when needed and as a last resort because nothing else will work.
• Do not apply pesticides or foliar fertilizers to anything if the temperature is over 85° F or if the combined temperature and relative humidity exceed 140.
• Most fungal diseases must be prevented, not eradicated.
• Subterranean termite reproductives swarm between March 1 and June 1.
• Do not use traps or pesticides to control yellow jackets or hornets before mid-August unless these wasps are on the front porch or in the mailbox or near family activity and pose a serious threat before then. (Wasps are beneficial as pollinators and because they feed caterpillars and other soft bodied pests to their larvae.)
• Japanese beetle populations peak on July 4 in central New Jersey.

PRUNING

• Prune spring flowering plants after bloom, summer and fall bloomers in dormancy (before new growth starts in the spring.
• Prune deciduous shrubs and trees in dormancy (after leaf fall in autumn or in late winter) to stimulate growth, in late spring to slow or curtail growth.
• The use of tree wound dressing on pruning cuts and tree injuries is unnecessary.
• Healthy broadleaf evergreens (azaleas, rhododendrons, holly, boxwood, et. al.) and yews can be pruned hard to areas below the last green leaves in early spring and recover completely.
• Remove the 3 Ds of pruning (dead, diseased, and damaged) anytime.
• Do not prune (or fertilize) woody plants between mid-July and mid-October.

SOILS and FERTILIZERS

• Do not fertilize (or prune) most woody plants between mid-July and mid-October.
• The best time to fertilize trees and shrubs is late March or early April.
• Soil is the medium in which we grow plants. Dirt is the stuff under the refrigerator.
• Having a soil test run is the only way to accurately determine limestone and fertilizer needs.
• Maintain a pH of 6.5 for most garden plants and lawns and 5.0 for acid loving plants.
• Compost is an awesome soil amendment! If you throw away coffee grounds, banana peels, or eggshells instead of composting them, feel guilty!
• The manure of any animal that does not eat meat can be used in a compost pile.
• Heavy (clayey) soils hold nutrients and pH levels longer than do the light (sandy) soils.

PLANTING AND MAINTENANCE

• The root flare at the base of the trunk should be even with surrounding grade. (If you can’t see a root flare, gently pull away soil until you find the first support root.)
• Holes for trees should be dug 3 times the diameter of the ball.
• Dig a hole for a tree only as deep as the depth of the root ball. Do not loosen the soil that will be under the ball.
• Remove twine and remove or fold back the burlap when transplanting balled and burlapped trees and shrubs. If removing burlap would break apart the soil ball, then make vertical slits through the burlap every 6 inches around the side of the soil ball after 1/3 of the backfill has been put in to support the ball.
• Butterfly (make a cut vertically through the root system 3" down from the crown) or slice (make 1" deep vertical slits every 3" around the soil ball) the root systems of container-grown azaleas, rhododendrons, and other plants with a matted root system before planting.
• Stakes and tree wrap are unnecessary for most newly transplanted trees.
• One year of recovery time from transplanting is needed for each inch (x) of trunk diameter. Give these plants special care and attention to watering for the first x years. Example: A 3" caliper tree needs 4 years to recover from transplanting.
• Fill kills. Piling topsoil over the roots of existing trees and shrubs is often fatal. (Death may be gradual so the addition of topsoil is not considered as a prime culprit.)
• Water all plants (indoors and out) in the early morning.
• Never exceed 3 inches of organic mulch on clay-based soils, 4 inches on sandy soils.
• Keep mulch at least 4 inches from the trunk/stems of landscape plants.
• Never use white marble chip mulch on acid loving plants.
• Keep all mulches (stone or organic) one foot from the foundation of the house. (This will allow the soil to dry at the foundation, hopefully reducing the probability of termite infestation.)

LANDSCAPING

• When you walk around your house with your left hip on the siding, your right hip should not hit a plant.
• Plant shade trees at least 30’ (preferably 40’) from the house. Plant willows no closer than 100’.
• Dogwoods live about 25 years, flowering cherries about 35.
• There is no such thing as a ‘good’ fast growing shade tree.
• If poplar (Populus spp.) trees are used in a landscape to provide a fast growing screen while slower-growing more desirable trees are getting established, plan to remove the poplars by the time they are 10 years old
• Homeowners shouldn’t grow fruit trees. (OK. This is just a suggestion! Fruit trees require skilled pruning and regular attention to pest control to produce a good crop and not serve as a breeding ground for insect pests that could infest local commercial orchards.) Blackberries, raspberries, strawberries, blueberries, grapes and jostaberries, are great fruits for the home garden.

INTERIOR PLANTS

• The light intensity at any window in the house is about ½ in January what it is in June. (Unless deciduous trees cast shade on the window in summer.)
• Overwatering is the leading cause of houseplant death.
• When repotting to a larger container, increase to the next larger pot. Example: Repot from a 5" pot to a 6" pot, not to a 10" pot.
• If a houseplant is infested, infected, or looks ratty, compost it!

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