Minnesota Gardening Calendar

Spring

General Season Tips:

•  Begin feeding bulbs with liquid fertilizer as they emerge from the ground.
•  Remove dead leaves from hostas.
•  Prune summer-flowering shrubs in early spring before new growth, since they usually bloom from new wood.

April

•  Uncover and remove winter mulch from roses, spring bulbs, and perennials.
•  Divide and replant overgrown perennials.
•  Till flower and vegetable garden soil and add composted cow manure, rice hulls, peat moss, or composted leaves.
•  Remove rose cones.
•  Plant frost-tolerant pansies and Johnny-jump-ups for early spring color.
•  Plant trees and shrubs as soon as the ground is dry enough for digging; late frost and snow will not hurt newly planted trees.
•  Apply fresh mulch around trees and shrubs for weed control.
•  Prune hedges and summer-flowering shrubs. Check for damage and remove broken branches.
•  Remove tree wrap when snow melts.
•  Fertilize trees and shrubs.
•  Apply crabgrass preventer to lawns.
•  Fertilize spring bulbs when foliage emerges.
•  Wait until the ground is frost free before removing mulch; if temperatures rise early in the season, remove part of the mulch but leave at least two to three inches.
•  Till or spade the soil deeply; if desired, add a slow-release flower-garden fertilizer.
•  Evergreens can be pruned at almost any time except late in the growing season.

May

•  Work fertilizer into vegetable and flower gardens before they are planted.
•  Fertilize roses and begin maintenance program against black spot and mildew.
•  Mulch flower gardens to conserve moisture and reduce weed growth.
•  Install peony hoops.
•  Protect gardens from deer browsing.
•  Plant summer-blooming bulbs.
•  Plant Minnesota Grown annuals and geraniums after frost is no longer a danger.
•  Apply pre-emergent weed control in shrub and planting beds.
•  Remove accumulated leaves and debris from underneath evergreens and shrubs.
•  Prune forsythia, azaleas, and lilacs after they have flowered; all spring-flowering shrubs should be pruned right after flowering.
•  Begin apple-tree spray programs after blossoms drop.
•  Make sure freshly planted trees and shrubs are watered weekly, especially during dry periods. Continue to water through the season.
•  Prune mugho pines when new growth is fully grown and soft.
•  Fertilize established trees, evergreens, and shrubs. Start a fertilizer program.
•  Rake, overseed, and fertilize the lawn. Avoid applying crabgrass preventer to newly overseeded areas. Seed new lawns while nights are still cool and the weather is wet.
•  Control dandelions and creeping Charlie by applying herbicide before heads are formed.

Summer

General Season Tips:

•  Deadheading (removing faded flowers and seed heads) directs the plant's energy to more flowering rather than to producing seeds. It's especially recommended for annuals.
•  Pinch back phlox, asters, and mums to make them more flower-productive.
•  Fertilizers are best applied to azaleas, rhododendrons, and blueberries in spring or early summer.
•  Use grass clippings as mulch around flowers. Do not use those that have had herbicides applied.
•  Leave the last rose blossoms of summer to encourage dormancy.
•  Apply slow-release fertilizer in midsummer to provide good plant performance until frost.

June

•  Stake larger varieties of perennials such as delphiniums.
•  Begin leaf-spot control on tomato plants and stake young tomato plants; late-staking contributes to blossom end rot.
•  Tie climbing roses to trellises.
•  Perform last pinching of chrysanthemums to promote compact, bushy plants.
•  Do last picking of rhubarb at month's end to allow roots to store energy for next season.
•  Mulch your garden after the soil has warmed up later in the month.
•  Fertilize lawns, flowers, and gardens, and continue weeding.
•  Prune and shape new growth on arborvitae, junipers, and yews.
•  Trim evergreens and hedges.
•  Prune pines, spruce, and fir trees in early to mid month.

July

•  Remove spring bulb foliage as it browns.
•  If spring-flowering bulbs aren’t doing well, dig up bulbs after the foliage has died and divide.
•  Before late summer, transplant and divide perennials.
•  Water, weed, fertilize, and harvest vegetables.
•  Trim maple trees.
•  Continue to water young trees and shrubs weekly.

August

•  Deadhead annuals for more blooms.
•  Divide irises and day lilies.
•  Complete evergreen pruning before the end of the month to prevent winter injury.

Fall

General Season Tips:

•  Plant perennials. Fall installation gives plants time to develop a strong root system. Most perennials flower in the spring; if planted then, they may not bloom the first year.
•  Split and replant overgrown bulbs. Dig up the bulb after the foliage has died and allow it to dry thoroughly. After drying, bulbs can be split and replanted.
•  Cut perennials to the ground after hard frost and use foliage for compost.
•  Gather fallen leaves for mulch and compost use.
•  Dig summer-blooming bulbs after the first killing frost and save for next planting season

September

T•  ake advantage of cool weather by planting trees, shrubs, and evergreens; use root-stimulating fertilizer to promote root growth.
•  Plant spring-flowering bulbs and work bone meal into bottom of planting holes for better growth.
•  Divide and replant perennials such as peonies and irises.
•  Water young trees and shrubs.
•  Now is the best time to seed new lawn, patch bare spots, and install sod. There isn’t as much competition with weed seeds now. Do it before September 15.
•  Plant chrysanthemums, pansies, asters, and flowering kale for fall color.
•  Apply weed-killer and fertilizer for lawn care, but not to newly seeded areas.

October

•  Clean garden beds and work compost into soil for spring plantings.
•  Remove dead annuals and add them to compost.
•  Cover tender roses before temperatures dip below 25 degrees.
•  Rake and recycle leaves for better air circulation and lawn-disease control.
•  Mow lawn until frost stops growth – tall, matted grass encourages snow mold.
•  rap young and thin-barked trees to protect against sunscald and animals.
•  Remove garden debris after the first frost to help minimize soil diseases and insects.

November

•  Early to mid-month, cover perennials with mulch to protect the crowns of the plants from the alternate freezing and thawing.
•  Put down an inch of hay or straw mulch over shallow-rooted perennials to prevent frost heaving (plants being pushed out of soil by freezing temperatures).
•  Plant large shade trees.
•  Water all the trees, shrubs, and evergreens, especially new plantings, just before the ground becomes frozen.

Winter

General Season Tips:

•  Install hardware cloth or other fencing that extends above snow level to keep animals away.
•  Check perennials for signs of heaving; if this occurs, re-cover with mulch.
•  Oaks, honey locusts, crab apples, pears, mountain ash, and hawthorn are best pruned now.
•  Keep evergreens and shrubs free of heavy snow.
•  Determine what flowers and planting techniques worked last season and plan accordingly.

March

•  Finish dormant pruning of ornamental trees.
•  Remove black-knot swellings on plum, chokecherry, and cherry trees.