Understanding Tree Fertilizer

Fertilizing your tree will provide a big impact to thefertilizers that would stimulate growth. Your
health of your tree in both the short term andconventional fertilizer should be applied in the fall
long term. More than pruning, more than anywhen roots are doing most of their growing.
other tree care service. There is a lot to knowHere are some common comments I hear about
about tree fertilizers. This article is meant to betree fertilizing:
an introduction to tree fertilizer. I highlyQ: These trees were growing here long before I
recommend you read my three other articles inwas here. They didn't need fertilizer before, why
this series: When to Fertilize trees, How to Applynow?
Fertilizers to Trees, and What Products to UseA: Ok, true. But, before you were here there was
for Fertilizing Trees.a natural balance of nutrient recycling. Now, the
You can compare tree fertilization to your ownsoil's litter layer is gone and replace with grass.
health care. Without it, you are not going toQ: Fertilizing is just going to make it grow faster,
wither and die tomorrow. But, with proper healththen I'll have to prune it more.
care (fertilization regimen) your tree will have aA: We just discussed that a good fertilizer
healthier, more full canopy of foliage. And, if aregimen doesn't stimulate growth. Quite the
good fertilization regimen is follow for a fewopposite, healthier trees will produce fewer dead
consecutive years, sick trees can return to alimbs over time, therefore, reducing pruning needs.
healthy state and regain extended life expectancy.Q: I don't like putting chemicals in my yard.
One of the biggest misconceptions I find peopleA: You shouldn't. But, what are you considering as
to have is a perception that tree fertilizationchemical? Fertilizers are less harsh that virtually
mostly make a tree grow faster. I can seeany cleaning supply you use and you actually get
where someone would come to this conclusion.that stuff all over your hands and up your nose.
Most of us get our experience in fertilizers fromAnd, if you get your timing right you can reduce
grass fertilizing. Grass fertilizers do result in fasteryour application rate dramatically. We target about
growing grass. Trees are different that grass.¼ lb nitrogen per medium sized tree per year.
Grass is in a constant state of growth and treesThat's 12 times less that what is recommended
only grow a few times a year; we call thesefor 1000 sq. ft. of lawn. Every other product we
growth increments flushes. The ultimate goal withuse is not chemical at all (see my article on what
trees is to time the right treatments so thatproducts to use for trees).
roots are stimulated to grow faster, but foliage isOne last topic I want to discuss before leaving is
stimulated to develop better (not grow faster).soil restructuring. Many of the trees if our urban
Timing is critical. Here are the basics you need toenvironment get left with small little islands of soil
know about timing: most root growth takes placeto grow from. There is a tool called an air-spade
in the fall; most foliage growth takes place in earlywe use to air-till the soil and mix organic matter in.
spring; there is not much growth in the middle ofTilling with this over-powered air compressor
the "growing season." With this knowledge youallows us to till the soil without destroying all the
should be able to deduct that fertilizing in thetree roots. This treatment is a huge improvement
summer would be a waste of time. During theto the soil structure and is great for all trees,
spring you should use unconventional treatmentsespecially those in limited rooting environments.
to stimulate healthy development not conventional