English: A screen planting of bamboo, used to ... English: A screen planting of bamboo, used to hide a roadway (Photo credit: Wikipedia)

First we have to determine why. Sometimes it is in the nature of the plant not to grow vigorously in the first year, such as Monkey Puzzle or Bamboo. More often the root system is not growing and establishing properly. There can be several reasons why:

  • Perhaps the top of the tree started growing before the roots after the tree was planted (this often occurs when daytime temperatures are warm and the soil is still wet and cold after planting), creating an imbalance in the tree. The demands by the top of the tree for water and nutrients are using up all of the energy resources in the tree, so the roots aren’t growing. Re-establish balance in the plant by providing 50% shade from the mid-day sun, and keep the soil evenly moist (not constantly saturated).
  • Over watering a newly planted tree will keep the soil wet and cold. Check the soil 4-6” deep for moisture content before watering, where the roots are, rather than looking at the surface. In addition, if the ground remains constantly wet oxygen is pushed out of the soil, which the roots also need for active growth.
  • Too much modification of the soil in the planting hole can also lead to problems for the root system. Sometimes water does not exit the planting hole as fast as we thought it would, keeping the soil wet and cold, because the soil porosity created in the planting hole is too different from the native soil. Maybe the roots are not eager to leave the planting hole because what is in the planting hole is too nice compared to the native soil. Over-fertilization with chemical fertilizers or animal manures in the planting hole can burn the roots, stopping them from growing until the excess nutrients have leached out of the soil.

The best solution when preparing the planting hole? Keep the fertilizer to a minimum, do not add more than 20% compost to a planting hole (about 2 shovels full), and fracture the sides of the hole before planting. After planting fracture the ground next to the planting hole (I use a digging fork), mulch with straw or leaves, and water only as necessary the first few weeks. Finally, order your plants now through the first of the year so we can deliver them to you at the beginning of your planting season.

If the roots are not growing vigorously the top of the plant will not grow vigorously.