Head Start for a Healthy Spring

Golf, Professional Turf & Tree Care
February 2016

Winter is a good time to get your trees in shape for the upcoming growing season. To do that, you'll need to focus on pruning, microbial soil care, tree nutrition, and soil pH.


Although light pruning of small limbs and removal of dead limbs can be done throughout the year, major pruning and large limb removal should be done in winter - or more specifically, when trees are dormant. Pruning, when properly done, will promote a nice burst of growth in spring.

Our 'rules of thumb' about tree pruning are:

• Never remove more than one-third of the tree's total height.
• Never remove branches unless they are one-third or less of the size of the tree's trunk.
• Never remove more than one-fourth of a tree's canopy per year.

These are general guidelines and different situations such as age and type of the tree as well a climate, may affect pruning requirements.

An Oak tree estimated to be over 600 years old.

Microbial Soil Care

Once pruning is completed, it's time to make sure your trees have optimal growing conditions. Trees growing in forests and in undisturbed areas thrive because their soils are rich in beneficial microbes. But, in urban areas where the natural layer of topsoil has been bulldozed or compacted during construction, trees struggle unless the microbes that were removed are added back.

Once in the soil, good bacteria not only protect trees against pathogens, but they also break down leaf litter and other debris to make nutrients more available to trees. Meanwhile, good mycorrhizal fungi colonize a tree's roots and spin off long, thread-like filaments (hyphae). The filaments significantly increase a tree's uptake of minerals, nutrients (particularly phosphorus, potassium and magnesium), and water. In some cases, mycorrhizae increase a plant's ability to absorb water and nutrients by 700 percent.

The most efficient way to reintroduce these beneficial microbes into a tree's root zone is to use BioNutrients Total-Pak Injectable for Trees.

Total-Pak Injectable is a dry soluble that includes seven strains of Ectomycorrhizal fungi and four strains of Endomycorrhizal fungi, multiple strains of beneficial bacteria, plus seven key micronutrients (Boron, Copper, Iron, Manganese, Magnesium, Molybdenum, and Zinc). I suggest mixing one 8-ounce Total Pak, per 50 gallons of water, then starting 2 1/2 feet from the trunk and injecting 1 quart 4" to 8" below the soil. Move 2 1/2 feet to the left or right, and repeat until you have gone full circle, then move 2 1/2 feet out toward the dripline and continue with the same pattern until you are just outside the dripline.


When taking care of trees, using fertilizers with low salt indexes is very important. Fortunately, Growth Products' fertilizers are chloride-free and have some of the lowest salt indexes on the market.

You can call any Growth Products Technical Specialist - to get help setting up a comprehensive tree fertilization program tailored to your specific needs. But, as a general rule, trees do best in the spring with a low nitrogen, high phosphorus, and high potassium fertilizer.

Despite the connotations of its name, Autumn Care 6-12-12 is one of my favorite fertilizers for late winter / early spring applications. Recover Rx 3-18-18 with Salicylic Acid is also another great choice. Derived from the bark of willow trees, salicylic acid, is a natural plant hormone that enhances tree growth, helps trees withstand environmental stress, and promotes overall tree vigor. Recover Rx can be applied as a drench or foliar spray in early spring and throughout the year.

Perfecting the pH

Last but not least, it's a good idea to test your soil's pH level now, before growth starts and the busy growing season is in full swing. Use a standard pH test to determine the soil pH, then check this against the trees' optimal pH range. If your soil is too alkaline, pH Reducer is a safe, non-corrosive way to adjust the pH downward. Unlike harsh mineral acids, pH Reducer, a natural Citric acid solution, will not burn tree roots nor change a soil's N-P-K ratio.

To find out more about tree care and about how the Growth Products' team can help you, please give us a call at 800-648-7626.