Editor’s note: Betty Cahill wrote about preparing your lawn for replacement here last week. Here is Part II.
You’ve decided to remove your cool-season lawn grass and replace it with either native grass or another water-saving grass species. The goal is to reduce outdoor summer water use and be part of the long-term solution of our limited Colorado water resources.
Good on ya; let’s roll up our sleeves and discuss the how-tos and what-nots.
Last week, we talked about the differences between warm and cool-season grasses, if swapping lawns is right for you, and helpful tips on saving water in your current landscape.
Timing
The expression “there’s no time like the present” is more than applicable to get started on a turf-replacement project. This applies both to first killing the existing lawn and then planting and caring for the new one.
The best time to get replacement turf planted and growing is when most of these grass types grow their best: in the heat of the summer. They need a good six to eight weeks or more of growth before nighttime temperatures remain cold in the fall. Target your planting by Aug. 1, certainly no later than Aug. 15.
If this planting window doesn’t work for whatever reason, make your plan now and over the next few months and try next spring. Do more homework in choosing your new turf type and the steps involved. If you’re partnering with a landscape professional, make contact now and get scheduled even if it’s a year from now.
Hiring help from a competent landscape company, turf specialty company or sod grower is worth the extra dollars if your budget allows. These companies can remove existing turf, add any needed soil amendment, rework irrigation if needed, grade the area, then seed, sod or plant plugs. Plan on spending approximately $4 to $5 a square foot for these projects with a professional.
Always check with your local municipality or HOA on changing out grass species or height rules, etc. Also check for current rebates for both low-water sprinkler upgrades and grass turf conversions.
Remember that there are up-front costs involved in a lawn conversion, from the seeds or plant material needed, installation, irrigation rerouting, and water to establish. Keep expectations in check knowing that the first season and subsequent years may require more time and effort for it to be a success.
Replacement lawn turf choices
Native grasses are defined as types that have been growing in Colorado and the North American Great Plains for centuries (or longer) and have become popular grass turf replacement choices. These include warm-season buffalograss and blue grama grass. Less well-known cool-season native species (also worth considering if correct for your conditions) include prairie Junegrass, streambank wheatgrass, and Western wheatgrass.
There are other excellent low-water grass turf options such as warm-season Bermudagrass and cool-season fine fescue.
Seed, sod and grass plug (smaller clumps of living grass) availability and pricing for grass turf vary, so speak with suppliers to find out current availability and pricing. Stop by your local independent garden center or co-op; some of them partner with local seed suppliers for shopping convenience.
(If using Buffalograss, consider choosing female Buffalograss seeds since they do not produce seed and flowers.)
Grass removal tips and procedures
Removing the existing cool-season grass is a must when replacing it with an entirely new grass species. Eliminating weeds in current lawns before the process is also very helpful for a better long-term result.
The methods of removal vary and depend on individual preferences, time frame and costs involved. There isn’t one perfect way; all require work and after-care in keeping weeds at bay and frequent watering for grass establishment. Know this: There will be weeds to contend with because anytime soil is disturbed, weed seeds rejoice and happily emerge and keep coming. They may be overwhelming, but if managed properly and often, the results with a new turf grass can be very gratifying and cost-effective in water savings.
Remember that once a new grass turf is firmly in place and growing well, it is important to water it at the new appropriate rate. If watering habits aren’t changed, then water expense won’t change, either.
How to remove or kill existing lawn
There are four ways you can do this:
1. Remove the old turf with a sod cutter (or hand dig), and be sure to remove all remnants of lawn near the edges. This method is the fastest.
2. If time is on your side, try smothering the existing lawn with organic matter like alternating layers of cardboard and soil to a depth of at least 6 inches. Let it sit for a minimum of six months or longer. After this time, till the entire area that incorporates the dead lawn for soil improvement.
3. Solarize the existing lawn with the sun and heat by covering the area with clear plastic for four to six weeks in the heat of the summer. Irrigate the area first since wet soil conducts heat the best. Bury the edges of the grass with plastic all along the border and use large rocks or bricks to keep it in place from high wind.
This is not recommended for areas where nearby tree roots will be adversely affected from lack of oxygen and water. Soil microbes and life beneath the soil may be affected as well.
4. Kill the existing lawn with a non-selective spray containing glyphosate at least two weeks prior to planting. This is a provocative method and topic, and for some people its use is not favorable under any circumstance; it is only mentioned here as another viable lawn-killing option.
Seeding or plug planting and care tips (for sod, see resources)
If using a landscape professional for installation, follow their care instructions to the letter.
For DIYers keep these suggestions in mind:
- Mow the dead lawn as low as you can before seeding or planting plugs. Planting in dead grass reduces weed growth and serves as a mulch for the new seeds or plugs.
- Heavily aerate the lawn to create lots of holes for the seeds or plugs. Seed at rates of 3-5 pounds of seed per 1,000 square feet and then rake the seeded lawn with the back of a metal rake to work the seeds into the holes.
- Plant plugs in a grid layout on 12-inch centers or closer. The closer plugs are planted, the better overall coverage, but obviously it will be more expensive. Seventy plugs, the average in a tray, will cover 70 square feet. Apply a slow-release natural or organic fertilizer after seeding or plugging on the same day; do not top-dress with any type of soil.
The first month requires focused attention and care to water the new seeds, sod or plugs. Plan on watering every four to five five hours during the day for a few minutes to keep the soil moisture even, not sopping water or creating puddles. Fertilize every three to four weeks but stop after Aug. 1.
Start mowing when the grass is 2 inches tall to encourage the grass to grow and spread. Remove weeds. Reduce watering to one to two times weekly after the grass has rooted well. Water well during the first growing season and during dry winters.
Resources
Buffalo Grass Lawn Establishment Using Seeds or Plugs: planttalk.colostate.edu/wp-content/uploads/2023/03/Buffalograss-Lawn-Conversion-2022.pdf
Colorado Native and Water Wise Grass Guide for Installation and Maintenance: coloradonativegrass.org/
Colorado Water Conservation Board Turf Replacement Program: engagecwcb.org/turf-replacement-program
Convert Your Turf with Dr. Tony Koski, Extension Turf Specialist and Professor, CSU: youtube.com/watch?v=BHfhLKPIL88
How to Remove All or Part of Your Lawn: planttalk.colostate.edu/wp-content/uploads/2023/03/How-to-Remove-All-or-Part-of-Your-Lawn.pdf
How to Sow a Blue Grama Lawn: highcountrygardens.com/gardening/planting-blue-grama-grass-seed-bouteloua-gracilis
Lawn Conversion Resources: planttalk.colostate.edu/lawn-conversion/
Native Lawn Establishment in Colorado: planttalk.colostate.edu/wp-content/uploads/2023/03/Native-Lawn-Establishment.pdf
Sodding a Lawn https://planttalk.colostate.edu/topics/lawns/1517-sodding-lawn/
Naming any grass turf company or chemical name is not a recommendation or guarantee of expectations and performance or accepting responsibility for use and results. They are named as references only; companies often have helpful websites for calculating seed, sod and plug pricing. Apologies if a nearby company is not mentioned in the links.
Betty Cahill speaks and writes about gardening in Colorado. Visit her at http://gardenpunchlist.blogspot.com/ for more gardening tips.
