By Cindy Kerson

Stage 1: In April of 2020, we laid kurapia Lippia nodiflora sod. We wanted to have a grassy area that would be good for the environment and look elegant. Kurapia is a low water user, a pollinizer, and is very low maintenance – you don't have to mow it. When we put the sod in, it was an especially hot period here in Napa and the sod is heavy and messy. We laid 1,100SF, which isn't really much and would likely have been installed by a professional team in half a day. It took us three long, hot, miserable days.

It was a winter with little rain and we were a bit concerned, but we were able to water the Kurapia the 2-3X/day necessary for the first few weeks. After that, we watered 3X/week, and then less and less. The roots grow as much as 6' long. In fact, we may have overwatered. We saw a few brown spots. And as is typical of uninformed gardeners – when brown add more water, right? In fact, we were causing a fungus because the stuff really doesn't want a lot of water.

We didn't put an irrigation system in because we figured it wouldn't be necessary within a year. Other than the spots we overwatered, the kurapia did very well. We watched butterflies and bees go nuts over it.

However, we noticed blue grass popping up within the broadleaf (kurapia is not a lawn – it is a broadleaf plant and knowing this is very important to its management). The area where we laid the sod was previously bark-mulched dirt and a few raised garden beds that were moved for the project. There were few weeds. So, where did the bluegrass come from? Hmm. We called the distributor and connected with the company that farmed the kurapia. Once seeing it, they fessed up – they found bluegrass weeds throughout a certain section of their farm and assumed we got some of it. They pleaded our forgiveness, which we granted, with this provision:

They were to lay new sod next spring, which would have been spring 2021. I planned to pull up the existing bluegrass infested kurapia and apply a preemergent herbicide to kill anything in the area, something not too toxic. In fact, we haven't used any product yet, because, sadly, we were all welcomed to spring 2021 after a very dry winter. On our property that's spelled dry well. Since it was now year two of low rainfall, our water stream dried up. So, we asked that the new kurapia sod not be laid until Spring 2022, and they agreed. This afforded me all season to watch what would happen if the kurapia got absolutely no water. We have a slight grade on our property, by county maps ~5% and where the lawn is laid it's likely ~1% grade. Over this summer, we watched the kurapia die off from the highest to the lowest point. In fact, today there are still a few areas that are thriving, having had no water or fertilizer. This is encouraging.

Stage 2: Over the last few days, we put cardboard down over as much of the area we could (we get only so many shipments with big boxes) and threw about 1-2” of compost on top. It's supposed to rain tonight, so that should pack it down a bit.

Finally, I wanted to put mulch on top of all of it and decided to let nature do it for me. We have a Chinese pepper tree and Crepe Myrtle that shed a ton of leaves this year. We'll simply blow them on top. See the image the next morning after applying the cardboard and compost, you can see it won't take long!

We'll be looking for more boxes to complete the process. In fact, it will be interesting to see if sooner or later is best doing this type of “lasagna composting”– maybe we'll put more down once a month over the next few months. Another consideration is to put compost and then plastic to solarize a different section. Let's hope for a good winter, with enough rain to support watering the new Kurapia until they don't need (or want) it anymore. I'm again looking forward to a nice green “lawn” area where bees and butterflies abound.

Napa Master Gardeners are available to answer garden questions by email: mastergardeners@countyofnapa.org. or phone at 707-253-4143.  Volunteers will get back to you after they research answers to your questions.

Visit our website: napamg.ucanr.edu to find answers to all of your horticultural questions.

Photo credits: Cynthia Kerson

References:

Oregon State Univ.-sheet mulching (lasagna composting)

https://extension.oregonstate.edu/gardening/soil-compost/sheet-mulching-aka-lasagna-composting-builds-soil-saves-time

UC Davis-Kurapia https://ccuh.ucdavis.edu/kurapia