Jessica Carlson 

Otter Tail County Master Gardener Intern 

As summer fades and autumn approaches, many gardeners are already planning ahead for spring. According to the University of Minnesota Extension, fall is the best time to plant hardy spring-blooming bulbs in Zone 4A. Planting should be done once soil temperatures fall below 60 degrees Fahrenheit but before the ground freezes solid. In most of Minnesota, this means planting between mid-September and mid-October. Consider filling your yard with golden daffodils, delicate crocuses, or dramatic tulips, the work you put in now will be rewarded with a bright and colorful spring.

Because Minnesota winters are harsh, bulb selection is important. Choose bulbs hardy to Zone 3 or 4 to ensure survival. Daffodils are reliable perennials that resist deer and rodents. Crocuses bring some of the earliest spring blooms and can naturalize beautifully in lawns or the edges of a woodland. Tulips offer dramatic displays but are often short-lived unless perennial or species types are chosen. Hyacinths provide fragrance and bold color near walkways, while snowdrops bloom in late winter and alliums add height and globe-shaped flowers that attract pollinators. When purchasing, look for bulbs that are plump and firm, avoiding any that are shriveled, soft, or moldy. Larger bulbs generally produce larger and more vigorous flowers.

Home and garden centers usually stock fall bulbs by late August.  If you are a garden enthusiast and want something out of the ordinary consider ordering from reputable catalogs or online suppliers. Extension advises shopping early for the best selection, storing bulbs in a cool, dry, and dark place until planting, and avoiding bargain bulbs unless you can check their quality carefully.

Proper site preparation is critical. Spring bulbs need well-draining soil and full to partial sun. Avoid low spots where water collects, since standing water can cause bulbs to rot. Soil should be loosened eight to ten inches deep and improved with compost or organic matter to enhance fertility and drainage. A balanced bulb fertilizer or bone meal can be added at planting, but nitrogen-heavy fertilizers should be avoided since they promote leafy growth at the expense of flowers.

Planting depth is also key. A good guideline is to plant bulbs at a depth equal to two or three times their height, so a two-inch tulip bulb should be planted about six inches deep. Bulbs should be placed with the pointed end up and the root end down, spaced several inches apart depending on the variety. Water after planting to help settle the soil and start root growth before winter. Once the soil begins to freeze, apply two to four inches of mulch such as shredded leaves or straw to protect bulbs from freeze-thaw cycles that can push them out of the ground.

Rodents and deer can cause serious damage to bulbs both in fall and spring. Extension recommends choosing naturally resistant bulbs such as daffodils, alliums, and snowdrops, which animals avoid. For tulips and crocuses, which are often eaten, you can protect plantings by placing chicken wire or hardware cloth over the soil surface until it freezes, or by planting bulbs inside buried wire mesh cages. Covering newly planted areas with a thick layer of mulch helps mask the scent of bulbs and reduces digging by squirrels. In spring, a barrier may be necessary to deter deer, especially in areas where browsing pressure is high.

Some gardeners consider planting bulbs in containers for added convenience or decorative flexibility, but this approach has drawbacks in Minnesota’s climate. Soil in containers freezes faster than ground soil, exposing bulbs to more severe cold that can kill them. Even hardy varieties often fail in pots if exposed to prolonged sub-zero temperatures. Container soil dries out more quickly, leaving bulbs without enough moisture to establish roots. Unless pots are stored in an unheated but sheltered location such as a garage or are sunk into the ground for insulation, bulbs planted in containers rarely survive outdoors through a Minnesota winter.

Folks who want months of color should plant a mix of early, midseason, and late-blooming bulbs. Snowdrops and crocuses provide the first signs of life in early spring, tulips and hyacinths follow with vibrant displays, and alliums carry the show into late spring. Planting in clusters of five or more makes for a stronger visual impact than lining them up in rows. Companion planting with perennials such as daylilies or hostas is also wise,  these plants help cover the fading bulb foliage once blooming ends.  Keeping the faded foliage on the bulb is pertinent as it allows the plant to photosynthesize and store energy in the bulb for next year’s bloom.

Since bulbs can only be planted once a year, it is important not to miss the fall planting window. As the University of Minnesota Extension notes, planting bulbs in autumn brings a burst of beauty in spring and rewards the foresight and effort put in during cooler months. With careful selection, proper preparation, animal protection, and timely planting, you can look forward to a beautiful display when the snow finally melts and the season of growth begins after the long winter.