What to do about the lawn
This is an unusual spring and we are all wondering what we should do as far as starting our gardens outdoors. We must first stay rational and realize that for sure we are going to get several nights that will be below freezing. This is Minnesota and people who garden here have a lot of common sense. We all know we need to hold off outdoor planting. However, what about our trees and lawn?
We have been fortunate in getting some rain this past week. However, we are over three inches short to begin this season so we need a lot of moisture. In regard to our trees, this drought can lead to tree decline, pest problems (pests attack trees which are stressed or dying), and permanent damage for young and old trees alike. Dry soils get colder in the winter and freeze deeper, which can kill roots. Dead roots are unable to take in water.
Even if damage was caused by the dry fall and winter, you can minimize its effects by keeping the soil moist, but not saturated. To check if your ground is thawed and assess moisture, push a kabob skewer or other metal rod into the ground. If the skewer can be pushed into the ground 8-10 inches, you can water. If the 8-10 inches is moist, there is no need to water yet. If the 8-10 inches is dry, watering is critical to the survival of the tree. When you water a tree do not pour the water around the base of the trunk. Rather water the whole area within the drip line (the area where the branch tips end) of the tree. The first 8 inches of soil is where most of the small roots of the tree are located which take up water. Water deeply one inch per week, rather than a little water each day.
In regard to watering lawns or turfgrass: turfgrasses are about 90 percent water by weight, so low soil moisture is a concern. However the University of Minnesota cautions homeowners not to jump the gun on a lot of lawn maintenance. Home owners typically rake lawns after snow melts to prevent snow mold. This year, we have no snow mold issues. Until the grass greens and start growing, doing extensive lawn care will do more damage than good.
You may be able to care for your lawn as usual this spring, if we get enough rain to bring the situation back to normal. However, if spring rains are not enough, you may need to bring out your lawn sprinkler much earlier than in the past. Water deeply (1 inch per week) so grass can develop a strong root system. It is very hard on the roots of grass to be watered, then let to turn brown, water again, and then let to turn brown. Brown grass is not dead; it is dormant and is not harmed by being brown.
Last week I wrote about pruning deciduous trees. As for the pruning of evergreens (conifer) trees, these usually require little pruning other then to correct some damage or control their size. Spruces and firs have lateral (side) buds that will sprout if the terminal (tip) buds are removed or damaged. They have one flush of growth each spring and can be pruned at any time, however, for the best results, now is also the best time to prune them if they need it.
Pines also put on a single flush of tip growth each spring and then stop growing. The flush of tip growth is called "candles." Pines do not have lateral buds so removing the candle will remove any new growth points for that branch. The best time to prune pines is when the needles are in a tight cluster against the side of the candle. Remove about 2/3 of the new candle, when the needles expand outward on the remaining 1/3 candle, they will cover up the pruning cut.
Arborvitae, junipers, yews and hemlocks grow continuously throughout the growing season and can be pruned anytime through the middle of summer. If pruned now the pruning cut can heal in cool weather as apposed to the heat and wind of the summer. Often times these shrubs will have brown branches on the inner core of the tree, this results when the sun is unable to reach these branches. This is called a dead zone. If the shrub is cut back so that the brown branches are exposed to sunlight, they will not turn green again. Pruning should be light to maintain the shape of the tree and care should be taken not to prune back to brown or dead branches.