One of the most cost effective alternatives to installing sod is planting grass plugs. If completely reinstalling sod in your lawn is not a practical option due to financial reasons or because there are only a few damaged areas, grass plugs might be a better option for you. Sod University has started a series on grass plugs with the use of a test plot we have been maintaining at our office since planting in May of 2019. The test plot is separated into two sections: one half is for CitraBlue®St. Augustine plugs and the other is for InnovationTM Zoysia plugs. This particular Sod University article focuses on our overall progress and other monthly updates since the beginning of December 2019. Our fall article left off with a status update in November of 2019. Refer to the previous articles to follow our progress since our day of planting in May of 2019: What are Grass Plugs and How to Use Them and Fall Grass Plugs Update.
Since planting the grass plugs in May of 2019, the CitraBlue and Innovation grass plugs have made tremendous progress with filling in the test plot areas. Take a look at some of the images below to see a visual representation of their growth throughout the past 10 months.
Pictured above from left to right: sod plug test plot in the months of May, July and September of 2019.
Pictured above from left to right: sod plug test plot in the months of November 2019, January 2020 and March 2020.
December Pre-Emergent Application
A good maintenance practice for sod or plugs is to apply a pre-emergent herbicide that prevents weeds from appearing. As discussed in a previous article called How to Use a Pre-Emergent Herbicide in the Spring, pre-emergents should be applied at least twice a year: in the spring before ground temperatures reach 55 degrees Fahrenheit and in the fall after temperatures begin to come down. We applied a granular pre-emergent herbicide called ProMate Barricade 0-0-7 with .22% Prodiamine on December 12, 2019, when temperatures began to drop in Charleston. This particular product serves as a combination of pre-emergent with fertilizer to control broadleaf and grassy weeds.
The pre-emergent was applied to only half the plot on both CitraBlue grass plugs and Innovation grass plugs. This was the experimental side of the test plot. The other half was left unaffected without a pre-emergent application. This was the control side of the test plot. The purpose of this experiment was to observe how much of an effect the pre-emergent had on the experimental side of the test plot in comparison to the control side of the test plot. In the photos below, you can see how we divided the test plot in half with twine and marked the ground with orange spray paint. Each half of the test plot contained CitraBlue plugs and Innovation plugs.
Pictured above: a table demonstrating the test plot of CitraBlue plugs and Innovation plugs that were treated with pre-emergent and untreated with pre-emergent.
We then used a granular broadcast spreader set at the appropriate flow-rate to apply the pre-emergent to half of the test plot while leaving the other half unaffected. The image below shows the pre-emergent herbicide inside the broadcast spreader. The video then demonstrates how it was applied to only half the test plot. You can see that we start at the orange line spray painted onto the ground to divide the test plot in half. When making applications, we walk in rows to evenly distribute the pre-emergent similar to mowing patterns.
Warm season turfgrasses including CitraBlue St. Augustine and Innovation Zoysiagrass enter dormancy during the winter months. Dormancy means the grass is not actively growing—however, it is not dead. Therefore, it is normal for warm season turfgrasses to turn brown in the winter. Charleston experiences a lot of unusual winters, so the CitraBlue grass plugs in our test plot did not go completely dormant whereas the Innovation grass plugs did. Temperatures stayed relatively warm and the climate was extraordinarily wet.
Pictured above from left to right: green CitraBlue plugs and dormant Innovation plugs in January of 2020.
Due to warm temperatures and wet soils that lasted throughout winter months, we experienced some fungus pressure. A small amount of disease is beginning to appear as the plugs start to green up more. Disease is often recognized around this time of year as turfgrass begins to come out of dormancy and green up. Areas that aren’t greening up, stay a straw/brown color and create noticeable patterns are physical symptoms of disease. We recently made applications of Spectracide Immunox Fungus + Insect Control, which hooks right up to your garden hose, to reduce the presence of disease. If you find that you really need a stronger fungicide to treat major issues in your lawn or plugs at this time, be sure to check out our family of fungicide products here.
Since the application of the pre-emergent we made in December, we’ve noticed some weeds that are growing on the control side of the test plot—but not very many. There is a slight difference between the control and experimental sides of the test plot from the pre-emergent application; however there is not a significant difference as we did not experience a lot of weed pressure this winter. We are experiencing some bermudagrass coming in on either side of the test plot though.
Pictured above from left to right: bermudagrass creeping into CitraBlue St. Augustine plugs and Innovation Zoysia plugs.
The CitraBlue and Innovation plugs have continued to significantly fill in areas of the test plot. There are hardly any spots that aren’t covered with grass on the Innovation side of the test plot, and CitraBlue’s stolons are growing longer and really connecting with other CitraBlue plugs. One of the next steps we will be taking soon is making another application of a pre-emergent herbicide.
Pictured above from left to right: a closeup of Innovation Zoysiagrass grass plugs and a landscape view of the Innovation area of the test plot in March of 2020.
Pictured above from left to right: a closeup of CitraBlue St. Augustine grass plugs, a long CitraBlue stolon and a landscape view of the CitraBlue area of the test plot in March of 2020.
If you are interested in grass plugs for your lawn this spring, you can check out our variety of premium zoysia grass plugs, St. Augustine grass plugs and others here. You can even buy the same Innovation grass plugs and CitraBlue grass plugs we used in our test plots.
For more information on the grass plugs and our progress so far, be sure to check out these previous articles: What are Grass Plugs and How to Use Them and Fall Grass Plugs Update. Our latest grass plugs update is located in the blog, Summer Grass Plugs Update. Lastly, be sure to read When is the Best Time to Plant Grass Plugs?.