By Sean Jordan, T.Ag.
So imagine you are sitting at the movies. The opening scene takes place
in the late spring, early summer on a golf course with happy golfers,
flying divots and smooth greens. The next scene is of the same golf
course the previous fall with the subtitle “8 MONTHS EARLIER.” Crew
members are cleaning up leaves, putting away benches and spreading
fertilizer. You may be a bit confused at this point since the title of
the film was “A Beautiful Spring.” If you were expecting this tale to
take place entirely in the spring, please understand that it would be
impossible to start telling the story half-way through without giving
some idea of what came before.
After so many months of staring at the snowy, bleak winter, it is just natural to want the turf to be green and ready for play as quickly as possible (not to mention the pocket books are getting hungry). This story will go over a few ways to wake the turf up earlier in the spring and put golfers back where they belong, on the course. 
Turf managers usually look to their fertility plan to bring things back to life after the thaw. Talking about a spring fertility program with the conversation starting at snowmelt would fail to address an important part of the subject; the way turf was put to bed for the winter months really dictates its performance the following year.
Feeding the turf in early fall (during the last few weeks of September) will start the recovery process from the recently endured heat and mechanical stresses of summer. It will also give the turf nutrients needed to build up its reserves through the fall when the second wave of root and lateral shoot growth is initiating. It is important to put nutrients in place early to make the most efficient use of them. As long as the plant is still photosynthesizing, it is creating and storing carbohydrates. Some natural signals such as shorter day-length and cooler temperatures during this period tell the turf that it is time to reduce top growth and start hardening off.
Applying large amounts of readily available nitrogen in late fall (usually anytime after October) increases the risk of fertilizer not being taken up by the plants as photosynthesis and carbohydrate storage will be significantly lower. An additional risk of fertilizing too late in the fall is the potential for an extended and unexpected period of warm weather. This combined with readily available nitrogen during the last few weeks of fall can cause flush growth, sending the turf into winter lush and more prone to disease.
Another method that many employ is that of applying fertilizer after the ground has frozen so that it will be available when the snow melts the following spring. This practice has several potential pitfalls as well. If the fertilizer is not soluble and stays on the surface, the material could wash away with surface water run-off. Mother Nature has a nasty way of showing us that she is in charge, such as a winter of heavy, accumulating snow followed by fast and furious melts that can leave much of our turf under flowing water. Another major drawback to applying nutrients when the turf is no longer able to take them up is the lag time for them to become available the next spring.
Classic charts on root and shoot growth show that cool season grasses are putting a great deal of energy into increasing their carbohydrate reserves (roots and lateral shoots) in the shoulder seasons, more so in the fall. When large amounts of available nitrogen are applied to the turf coming out of winter to produce brilliant colour, it does so with several costs. Top growth kicks into high gear resulting in more mowing in mid-to-late spring when the grass plants are already growing well due to warmer soils. This induced growth surge also taps into the carbohydrate reserves in the roots and lateral shoots that the plant worked so hard to stock up over the past several months. Do not assume from this last part that nitrogen fertility in the spring is a bad idea; it just has to be planned well and timed according to how the grass is reacting to the weather.
Application timing can be an issue depending on preferred materials and the composition of grasses in the turf. A possible hazard to applying nitrogen in a granular form to cold turf is speckling. This can occur for a couple of reasons: poor distribution of the nitrogen component of a blended fertilizer that was applied with too little material (usually off-rate); or different species of grasses coming out of dormancy at varying rates and therefore reacting to the nitrogen application with distinct differences. Alternatively, foliar applications of iron and/or nitrogen at low rates can change the hue more toward green without the risk of the turf looking like a Dalmatian. Applying fertilizers in the early spring when the soils are still cold or waterlogged can also lead to loss, which equates to wasted labour and expense.
Just because our conversation to this point has surrounded fertility, not everything that makes grass green is fed to it. If the turf is lucky enough to come out from under snow cover just drowsy, and not dead or thoroughly beaten with snow mold, there are several options to green it up without applying unnecessary amounts of nitrogen early on.
Looking at the natural progress of turf in the spring, it is a given that as the soil warms up, greener colour follows. So how do we use this to our advantage? In the fall or early spring, an application of dark sand or organic fertilizer can capture the heat of the sun to help this process. Also, if you are in a situation of having several staff on hand early in the season, you can utilize covers at night to keep the heat captured by the turf during the day from re-radiating out in to the cold night air. The nice part of the latter practice is that you can get away with only covering on clear nights. You just have to remember to uncover during the day so the plants have a chance to soak up some sunlight to photosynthesize and warm up.
Another pleasant side effect of the soil warming is increased microbial activity. The microbial community has had a long winter, too, and is eager to start working again, making soil nitrogen available to the turf. Fortunately, the roots were awake long before the microbes, so they are ready to start taking up the nutrients as they become available.
By this point your mind is probably wandering to thoughts of the spring sun shining and the first cut of the season, so we’ll bring this segment of our story to a close.
While there is time yet before the snow has completely gone away, some planning should be done while the end of last season is a not-too-distant memory. Working towards a “Beautiful Spring” next year by planning labour, materials and timing can only benefit the turf in the end. Now all that is left is to survive summer. That we will talk about next time.
Print this page
