Winter / December to March
The winter solstice, which is at the beginning of winter, marks the shortest daylight of the year.
Perennial flowers, shrubs and trees are taking a break for winter, and so can you. Stroll through the landscape looking for potential decorating items.
Check for dried flower stems suitable for use in decorative arrangements. Stems may have lingering dried leaves or interesting seedpods. Snip evergreen boughs for wreaths or grouping on flat surfaces such as part of a centerpiece. Corn, beans and tomatoes need even warmer soil temperatures to germinate, or about 55 degrees. Wait until after the last frost to plant cucumber, pumpkin, squash or eggplant seeds because they need even warmer soil temperatures (minimum 60 degrees) to germinate.
Spring / March to June
The vernal equinox, with daylight about 12 long, kicks off spring.
Read seed packet labels to determine proper planting time for your USDA zone. Seeds like spinach, peas or broccoli can germinate in soil temperatures as low as 40 degrees Fahrenheit. Carrot and lettuce need soil temperatures no lower than about 45 degrees to germinate.
Summer / June to September
The summer solstice, which is at the beginning of winter, marks the longest daylight of the year.
Plant sweet potatoes in early to mid-summer. Seed second planting of snap beans in mid- to late summer.
Water garden plants deeply in hot temperatures, and water less often to reduce affects of drought on plants.
Fall / September to December
The first day of fall marks the autumnal equinox with daylight about 12 hours long.
In the flower garden. Clear wilted annual flowers from flowerbeds unless you are leaving spent annual blooms such as impatiens or petunia to self-seed. Dig up tender bulbs such as tuberous begonia and gladiolus to dry and store indoors over winter. Plant spring-blooming bulbs, like daffodils or tulips. Mound soil or fallen leaves around tea roses to protect against cold winter winds.
Perennial flowers, like coneflower and coreopsis, may be left to self-seed. Spent blooms from coneflowers are also a treat for birds and can remain in the garden though they may look a little scraggly. Cut back perennials to the ground, including peony. Overall, fall is a good time to neaten up and make plans for next year. Perennials may also be divided in fall if desired. I prefer to divide perennials in the spring when the first new growth appears so I can see areas of the flowerbed that would benefit from new plantings.
In the vegetable garden. Some vegetables such as tomatoes and peppers will keep on growing until the first hard frost. Snip off new blooms to force attention to maturing vegetables. If frost is expected, cover the plants with a layer of plastic. Remove the plastic when the sun has melted the frost from the ground.
Remove plants after they die back. Use a rake to rough up the soil (or turn the soil with a shovel or roto tiller) and then spread 2 to 4 inches of collected leaves over the soil. Keep the leaves moist until late fall to promote decay. If snow or rainfall is not present, then moisten the leaves and soil, and turn the leaves once or twice a month.The leaves are then worked into the soil in the spring to had natural nutrients to soil.
In the herb garden. Dig up and divide herbs like chives, or pot them to bring indoors.
Clean and lubricate tools. Clean power tools. Drain garden hoses and store indoors. Allow gasoline-powered tools to run to empty the gas reservoir. Check this article for guidance on preparing the lawn mower for winter storage. Learn how to clean and store clay pots here.
Rake and save leaves for leaf mold.