Autumn: A Cool Time to Plant Grass

In southern California Winter, Spring, Summer, or Fall (sounds like the making of the song) is a good time to plant grass.  But, right now is a strategic time to install a lawn not only for the holidays but for the rest of the year.

Weather is an important factor as to when a lawn could or should be installed. For most places in the country, you’re limited to Spring or early summer.  However, southern California has a weather utopia and as we are going to find out autumn is a great time to install a lawn as there are secrets that lay beneath the soil.

Growing up in southern California it’s hard to imagine not having a green lawn for the holidays.  That’s why many people will go the extra mile to ‘green up’ their lawns that turn deciduous in fall/winter by reseeding with an annual Oregon rye seed.  The concept is quite simple.  Six to eight weeks before Thanksgiving mow your lawn short (removing thatch is a nice extra step),  sow annual rye seed at a rate of twenty (20) pounds per thousand square feet, then lower your property value by 30% covering it up with steer manure (do you really know where steer manure comes from?  Piu!), water and in six weeks you’ll have a green lawn.  Typically we only see this done to St. Augustine and Bermuda grasses when they go dormant.

Pro-Tip: It’s possible to force a lawn into dormancy in autumn by dethatching and aerating.  Don’t fertilize the lawn at this time; wait until Mother Nature starts to wake it up before feeding it.

Green All Year ‘Round. The Marathon Family of Grasses, Pureblue Lite and Ryeblue Lite are turf grasses that stay green all year.  Each has characteristics that are suited for your lifestyle: active lawn games/parties (don’t forget to invite me), occasional use, pets, or no activity at all.  By planting these turfs in autumn you’ll see an amazing thing happen until Spring – nothing! That’s because the magic happens below the soil surface.

Ever wonder why some football fields have beautiful green grass to play on while it’s snowing on the sidelines (Green Bay’s Lambeau Field was the first NFL to install a turf heating system)?  Or, why golf greens can be so green in the dead of winter and all the fairways are brown from dormancy (ie. PGA Southern Hills Country Club (SHCC) in Tulsa, Oklahoma)?  On a professional level below the soil surface are grids of heating elements warming the soil up to 64 degrees or so.  That doesn’t sound like much but it’s plenty to activate grassroots to keep the plant growing even when air temps are much lower.

On a homeowner level, the same concept applies but we’re at the mercy of environmental conditions which is always favorable in southern California – no heating elements needed.  Soil temperatures are always warmer than air temperatures.  This is the perfect combination for subterranean root growth.

Fun Fact:  Heating up soil 5”underground to only 38 degrees will actually heat it upwards to 65 degrees in about 7 days. As it slowly heats it gathers the warmth to keep roots nice and cozy so they can actively grow when it’s cold outside.

It‘s possible for the soil to freeze but certain conditions must be met first.  There must be a cold rain or wet snow for moisture to creep into soil pores followed by a hearty snowfall that just doesn’t go away.  Even under harsh inclement weather we normally won’t see much more than a couple of inches freeze and a deep, well-rooted lawn should reach upwards of 6” plus when established. Cool temps are heavy and fall to the ground, but, since there are air pockets in soil heat rises at a much slower rate keeping the soil warm.  This is important for soil microbial activity for it to stay alive.  In the wild, the soil needs to stay warm for animals to stay alive.

Question:  Do you call the season Autumn or Fall?

Warm soil is the perfect gift for roots to get a hug and they’ll actually continue to grow! On the surface, though, you won’t see much activity.  That coolness we talked about earlier sits on grass blades and tells them not to grow because it’s just too cold.

The preparation and installation for an Autumn lawn are the same as any other time of year.  The biggest challenge is to make sure the weeds have been treated with something like glyphosate before planting (solarizing is useless this time of year).  Killing weeds in cool weather takes a few days longer than normal so plan accordingly.

Next you’ll pull out the existing grass and weeds.  Now, fortify with a quality compost with as little or no steer manure in it as we don’t want the salts to burn the roots.

Don’t forget that all-important step of even irrigation distribution.  Those sprinkler heads need to be from the same manufacturer (your choice) and the spray must be overlapping for head-to-head coverage.  Keep in mind to follow the rules for watering new lawns but don’t overwater if it happens to rain.  On a side note, concrete walks and drives don’t grow so be mindful to direct your sprinkles just to the lawn.

Pro-Tip:  When preparing your lawn for planting it’s important to rototill quality soil amendments evenly for 2 major reasons: (1) even distribution equals even water holding capacity. (2) Clumped compost will rot encouraging mushrooms to grow.

By the time early spring comes around you’ll see a spurt of growth unlike none other.  It’s at this time you’ll want to put down fertilizer and a pre-emergent.  This is can be a combination of fertilizer and a pre-emergent weed suppressor/killer or two separate products.  This is an important step because in your lawn prep you most likely killed off the beginning of winter weeds, not summer weeds. Who knew there was such a thing as summer and winter weeds, right? This process will put a protective coating over the soil surface impairing summer weeds to pop through. Then, follow through with feeding your lawn as recommended.

By installing a lawn during Fall you’re giving your yard a kick start like you can’t imagine.  You’ll see very little growth until Spring, but, that root system will be so established you’ll be able to do all things most people will have to wait to do.

Nick Federoff, ThingsGreen.com
Syndicated Radio and PBS Television Host