Fertilizer Aisle at Garden Center

Fertilize most landscape shrubs and trees in winter or early spring with a granular 10-10-10 at a rate of 20 lbs. per 1,000 square feet when the ground cover is dry. A 19-19-19 fertilizer is distributed at 10 lbs per 1000 square feet. Distribute within an area 3 feet out from the trunk or shrub crown and 5 feet beyond the end of the branches. Most of us don’t care to haul a 20 or 40 lb bag of fertilizer from one tree to the next. A one pound coffee tin holds about 2 pounds of fertilizer.

Encapsulated slow release fertilizers deliver the nutrients soil temperatures are warm. Each capsule, called a “prill”, is soil moisture and temperature sensitive. The prill meters out a precise amount of the 3 key nutrients (nitrogen, phosphorus and potassium) over a 3, 5 or 9 month time period. In the warmest areas of the U.S., slow-release fertilizers deliver in a shorter time period. Prolonged drought periods also interrupt prill release. Overwatering meters out fertilizer faster and plants often appear nutrient-starved by late summer.

Water soluble fertilizers such as Miracle-Gro™, Miracid™, Jacks®, Peters®, or Hollytone® are great alternatives. These fertilizers are effective for 4-5 weeks and are usually applied bi-monthly from late March thru mid-August on a 6-8 week schedule.

In most areas spring rainfall is adequate to water the fertilizer in and leach it down to the tree/shrub root zone. Otherwise, you should irrigate to carry down whatever product you’ve applied.

Keep in mind that these are general recommendations and some plant exceptions apply.