Spring | Summer | Fall | Winter

General Spring 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.

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.

September

• Take 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.
• Wrap 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.

General Winter 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.

This calendar is provided as a service to consumers by members of the Minnesota Nursery and Landscape Association ( MNLA)