Everyone wants to get into the yard and garden now with at least a hint of warmer weather…. Leif’s article from the Northfield News last Saturday highlights the different sequences for success in the garden………
A long winter and a scattering of nice days in April have most gardening enthusiasts eager to till and plant. The sequence of what you plant first and what you delay until later may determine the difference between success and disappointment.
April and the first half of May is a great time to plant cool season varieties of annuals, as well as trees and shrubs. Pansies, petunias, snap dragons, dianthus and alyssum are good choices for early season flowers. Cabbage, broccoli, kohlrabi, potatoes, radishes, lettuce and spinach are fairly safe early season vegetables that should prosper in cooler soil temperatures.
Almost all the trees and shrubs that are commonly sold for use in Minnesota landscapes can be safely planted prior to May 15th. This would include anything rated hardy for zones 3 and 4. If you have decided to experiment with zone 5 or 6 trees or shrubs, it’s best to wait until later in May.
Be a bit cautious about the varieties you chose. Some larger general merchandise retailers offer some varieties that may be more appropriate for milder climates than what we experience here in southern Minnesota.
Warm season annuals such as impatiens, begonias, coleus and such are best planted after May 15th-20th, when soil temperatures have warmed nicely. The same holds true for warm season vegetable crops such as tomatoes, peppers, squash and cucumbers. On southern exposures soil temperatures may rise sooner, but there remains the danger of frost. The average date of the last frost is around May 10th to 15th in the Northfield area, but if your garden is in a low spot in the landscape it may be easier for frost to occur at later dates, since the coldest air at night slides from higher elevations down into the low areas. I have heard these low areas referred to as “frost pockets”.
If your garden soil warms nicely due to good sun exposure, but you suspect you may be in a frost pocket, it could be beneficial to use a “tent” to protect your warm season annuals from a rogue late frost, until they establish and the danger of frost has passed.
I have noticed a rather large number of dead native elm trees. A series of droughts and warm winters have stressed trees, and made it easier for Dutch Elm beetles to survive to the next season. Be very careful when removing dead trees. Rotten or damaged branches can easily break off in the process of felling the tree, and come shooting down to injure the person sawing, If you have any doubts about the safety of doing the removal project yourself, contact a tree removal professional who is fully insured for liability, property damage and personal injury. They have the equipment, training and insurance necessary to do the job safely.
Because of the devastation from Dutch Elm disease, many people are still reluctant to plant the many excellent hybrid disease resistant Elm varieties that are now available. Wait no longer! Fifty years of research and development have produced many elms that are extremely resistant to Dutch Elm disease. Varieties that are fairly widely available are Accolade, Discovery, Danada Charm, Cathedral, Triumph, New Horizon and Vanguard. Princeton is a new release but available only in very limited quantities.
People for whom we have planted these elm trees report that they have done very well. Growth rates are very good once established and Elms can grow in almost any soil, so they are very versatile. If you are looking for shade in a hurry, consider a hybrid disease resistant elm.
Plant Spotlight: Redbud. (Minnesota Strain) This seldom planted flowering tree produces an explosion of stunning purplish blossoms every spring. We are at the northern edge of the range for Redbud, but the Minnesota strain has been pretty successful here in the Northfield area. Hardy once established, Redbud is very disease resistant, maintains nice foliage through the growing season. Redbud prefers well drained soil and full sun to part shade. Try to avoid areas with alkaline soil. Grows to 20 feet tall and 20 ft. wide, but most I have seen in this area seem to be smaller than the size ratings.
