October is your last and most important chance to feed your lawn and ready it for next spring. Make it count! Says Shay Lunseth, co-founder of Organic Lawns by LUNSETH in Minneapolis.
Fall introduces new beginnings. A new school year where we take in knowledge to grow our minds and prepare for a bright future. Fall, also, brings the end of the growing season, where we can and store the fruits of our labor as we head into winter. Taking care of a lawn should be thought of similarly. What we do now greatly affects our grass next year.
Right now is the most important time to apply organic fertilizer for two reasons. First, when grass prepares to go dormant, it stores carbohydrates in its stems and underground root system. Late-season fertilization provides the plant more food to store during dormancy, which helps your turf green up in the spring and extend its greenness into the summer and fall.
In contrast, spring fertilizer feeds the actively growing plant, but not the root system. The growing plant may achieve a desirable green color in the spring, but the fertilization will, also, diminish the turf root’s reserved energy. The weakened grass will experience hardship entering into the hot summer months. Fall fertilization minimizes shoot growth and strengthens root growth to prepare your turf for the stresses of summer weather.
A good root system can:
- Allow a lawn to be more drought tolerant
- Creates strength to better withstand heat, ice and other negative environmental factors
- Better protects grass from insect and disease pressures
The second reason to fertilize cool season grass this fall is to take advantage of the beautiful weather that provides ideal sunlight and soil conditions to strengthen roots and store nutrients for next season. Roots prefer to grow between soil temperatures of 58-65 degrees. In the Midwest, soil temperature lowers much slower than air temperature.
Even when air temperature is as low as 35 degrees, the soil can reach 60 degrees.
Which Fertilizer should I use in the fall?
Look first for a 100% organic, slow-release product. Quick releases of nutrients will allow a flush of growth, which can create excess thatch and an environment conducive to disease and rodent pressure. Note that ‘Natural’ or ‘organic-based’ fertilizers may include synthetic source material and are not 100% organic. Here are the benefits of 100% organic fertilizer.
100% Organic Fertilizer:
- Does not require water
- Nutrients slowly released
- Lower leaching and runoff potential, nothing is wasted or washed away
- Multiple nutrients (macro- and micro-), as well as organic matter
- Improve soil structure for better water-holding capacity
- Naturally feeds earthworms and soil microbes, thus increasing their populations
- Has lower salt content
- Helps turn your root zone into a self-sustaining environment that can work on its own
- Can be applied infrequently at high rates
- Decreases fertilization needs because nutrients are stored in soil for future use
- Less thatch accumulation
- Water soluble
- Immediately available to plant roots, if plant does not use then are lost in soil quickly
- Higher salt index & leaching with runoff potential
- Uniform – every bag the same
- Creates short, weak grass roots that are ‘hooked’ on synthetic food
- Lawn ecosystem does not know how to work on its own
- Creates a lawn more susceptible to drought and disease
Organic fertilization combined with an application of compost or compost tea in the fall produces favorable conditions for root growth. Think of compost tea as the “espresso” version of compost. It contains all the beneficial bacteria of compost minus the organic matter and labor cost.
When made correctly, compost contains bacteria, fungi, protozoa and nematodes that add nutritional value to the lawn ecosystem. Composting in the 1st year of a new organic lawn care program supplies a vital alternative of beneficial microorganisms to a lawn that craves synthetic fertilizers.
Fall fertilizer and compost applications can be successfully completed very late in the season. The optimal time in the Midwest is after the last mow and can be done as late as early November.