Spring

Early Spring (Mar-Apr):

Remove debris from the crown of shrubs and any deadwood. Remove debris from crevices in shrubs (azaleas tend to collect debris in the crooks of branches.)
Prune back shrubs if they have not leafed out such as Spirea, Butterfly bush, Roses. Do not prune early flowering shrubs.
Thin trees and remove split or broken limbs.
If you are planning a new garden or replacing an old one, now is the time to get started if you haven’t already. This way you can get the plants in the ground before the hot days of summer arrive and you can take advantage of those spring showers.
Begin planting shrubs and perennials. The earlier you shop the more likely you will get the cream of the crop and the best choice in varieties.
Prepare vegetable garden soil. Plant early crops.
Remove excessive leaves from gardens and the dead foliage of last year’s perennials. Remove any remaining annuals.
Remove early weeds.

Spring (late Apr- June):

Mother’s Day is the recommended first day to plant annuals outside in our area. Earlier can be done but plan on checking the weather and be prepared to protect the planted annuals in case of frost.
The real weeding begins. Pointers: get the roots to avoid the production of new shoots, pull weeds before they flower and spread their seed and weed consistently throughout the season. Weeding once a month with a bi-weekly pull of those flowering will keep them under control
Mulch as soon as you have weeded. Mulch should be 3-5” thick. Mulch does not eliminate weeds from germinating on top but it does make the pulling of these weeds easier. Keep the mulch at least 3-4” from the stem/trunk of plants

Summer

Keep the garden watered. A short thunderstorm does not moisten the garden sufficiently as most just runs off. Usually only the mulch appears wet. If you feel the soil under the mulch it will still be fairly dry. Supplemental watering is vital.

Annuals & 1st year Perennials & newly planted shrubs & tree: Annuals & 1st year Perennials have the smallest root system in the garden so they must compete with the other plants for water. Ideally these need a thorough watering every other day. The equivalent of ½ inch of rain with each watering. New shrubs & trees will need a thorough watering every other day as well.

Perennials, Shrubs & Trees(planted more than 1 year): These may need supplemental watering if a drought lasts longer than 2-3 weeks. A thorough watering is key. You want to get the water down 4-6” to strengthen the roots.
Keep the weeds pulled as they also compete with your garden plants for water and it seems that they take most of it!

Water when dry to the touch, but water thoroughly. A sprinkler on the area for at least 45 min to 1 hour is a good watering.

Deadhead spent flowers. This will strengthen the plant and your plant will flower more profusely.

It’s important to keep your garden watered, although the frequency should be reduced. As days shorten and temperatures drop, plants require less water. Best bet: use your hand and dig a hole next to the outer edge of the root ball and feel for moisture.

A good base of mulch keeps the ground from freezing and thawing. This back and forth is more damaging to the roots of plants than staying frozen all winter If you mulched in the spring you may only need a touch up now. If your mulch is less than 2” thick you should probably top it off with another inch. Just remember to keep the mulch at least 6” from the trunk of trees and shrubs. Some little critters would cozy up under the mulch and nibble at the bark all winter long. This could cause the death of the tree or shrub. But before applying mulch, make sure you pull those weed and be sure to get the roots. If you leave the roots behind, expect those that are perennial weeds to come back with a vengeance in the spring. You can use shredded leaves as mulch as well.

Early to mid-Fall is a good time to add new shrubs & perennials to your garden. Make sure to water and mulch well. Plant your Spring flowering bulbs before the ground freezes.

If you don’t mulch with leaves, you may want to add those mulched leaves to a compost pile or start one.

Cut perennials back once the foliage turns brown. You may want to leave the seed heads on some, such as Black Eyed Susan and Echinacea until spring so that the birds can enjoy them for winter meals. Some woody perennials such as Lavender, Hypericum, Caryopteris, and Russian Sage, to name a few of the most popular, do not like to be cut shorter than 6”.

It’s a great time to divide most perennials. Dig generously out from the main clump to get as much root as possible. You can then divide the clump using the the spade, knife or saw depending on the root mass. Make sure to keep them watered.

Trimming & pruning can be done now. Prune out dead limbs early, but best to wait until the foliage is down to prune for size reduction or the rejuvenation. Always check to learn the correct way to prune your particular perennials and flowering shrubs. There are some that are particular!

Make sure you remove all water from irrigation lines and hoses. Store hoses indoors for added protection. Ceramic and Clay pots can break if left outdoors where they can catch rain and freeze. If you can, bring them indoors or store upside down.

Snow: When shoveling snow do NOT pile it on top of your shrubs. This can cause breakage of the branches especially the compact, dwarf shrubs such as Gumpo Azaleas, Dwarf Weigelia, Pieris Prelude, etc.

Freezing & Thawing: Plants are more affected by freezing and thawing than by a constant freeze. So to help prevent this make sure you your garden is mulched. This will help to keep the soil temperature more even.

Wet vs Dry: Going into the winter it is better for your ground to have some moisture in it rather than to be dry. So if we are having a dry fall it would be wise to wet the ground prior to the ground freezing. When roots get frozen and there is water in the ground the temperature around the roots remains the temperature of the ice. That is 32 degrees. If the ground is dry then the roots are surrounded by air. Air temperature can dip below 32 degrees and therefore exists the possibility of root damage.

Wilting: There are various shrubs that look wilted when the temperature slips below freezing. One is Aucuba. Don't worry they will perk up when the temperature comes back up. It may sometimes result in black edges or spots on the leaves. In spring just prune and the plant will bounce right back.