September

•    Now’s the best time of the year to start a new lawn, lay sod or overseed an existing lawn. It’s also a good time to dethatch and/or aerate the lawn.
•    Resume fertilizing the lawn and, if needed, add lime. If you’ve still got weeds, spot-spray them with a broad-leaf weed-killer labeled for lawn use. If they’re really bad and all over, use a weed-‘n-feed product.
•    Replace flagging annuals with pansies, mums, ornamental cabbage/kale or other fall or cool-season plants.
•    Plant new trees, shrubs, and perennials. It’s still a little early to plant spring-flowerings bulbs, such as tulips, daffodils and hyacinths. October is better… late September at the earliest.
•    Divide existing perennials, except fall-blooming ones, and transplant existing shrubs that need to be moved.
•    Stop pruning and fertilizing trees and shrubs as they begin heading into dormancy.
•    Move houseplants back inside after checking for insects and hosing down and treating with insecticides, if needed.
•    Pick bagworms off arborvitae and other woody plants if you didn’t control them earlier with sprays.
•    Scout for pest problems and treat as needed. Watch for beetle grub damage to the lawn; scale on magnolia; galls on spruce, and mites on evergreens. Reseed lawn grub damage or use Dylox or Sevin if you’re dead set on killing the grubs.
•   If you’re overrun by spotted lanternflies, they can be trapped, sprayed, or stomped. Penn State Extension has an excellent rundown on your year-round control options as well as advice on when to consider fighting back.
•    Have soil in lawn and gardens tested if you haven’t done it in the last couple of years or if plants are struggling.
•    Great time to start a compost pile with spent garden plants, grass clippings and leaves that soon will fall.
•    Take hardwood cuttings of shrubs you want to propagate.
•    Keep plants well watered – especially newly planted plants – if rain isn’t sufficient.
•    Continue deadheading spent annual flowers and trim off spent flower stalks of perennials after they bloom.
•    Dig new beds and/or improve the soil in existing beds. The weather is cool and the soil is usually drier now than early spring.
•    Harvest vegetables, pull spent plants and fill empty space with lettuce, radishes, spinach or carrots or plant a winter cover crop.
•    Continue feeding fish as long as they’re active and continue to trim dead and ragged plant parts in the water garden.
•    Don’t panic if you see pine and spruce trees begin to drop their innermost needles. This is normal.
•    Continue spraying program for roses but no fertilizing any more this season.