This summer in Northern California has been pretty hot. I noticed a few areas of my lawn were more effected than others, specifically brown areas where my sprinklers weren’t getting enough water. Yes, I could re-arrange the sprinklers or add a few more lines, but I’m just not up to that task. During some internet browsing I read about topdressing a lawn. I read about the nutrient benefits but also about water retention. A few weeks ago I decided to take some of my old compost (about 2 years old) and try an experiment.
I took about a cubic yard of compost (yard clippings, kitchen scraps, chicken litter), screened it, and sifted it onto my lawn with a shovel and then used the back of a garden rake to distribute it evenly over a few of the areas that were brown. I had also read that you can use 1 part compost and 1 part sand as a top dressing to help even out dipped areas in a lawn (slowly adding 1/4 – 1/2 inch of material until it evens out the dip). Well, I have an area around my water meter that is sunk down a little and I’d like to raise it up. I mixed the compost with some sand and spread 1/2 inch in a foot radius around the water meter.
Well, about a week and a half later I couldn’t believe my eyes. The 1 foot radius area around the water meter has sprung to life. The grass was lush green and had grown about 1/3 as high as the surrounding grass! You may not be able to see it in the picture, but the transformation was extremely obvious. Unfortunately I didn’t see the same results in the other areas of the lawn. The only differences between the two applications were:
This area tends to get more water than the other areas I applied the top dressing.
- The other areas didn’t include any sand.
- I applied considerably more top dressing to this area (to build up / level the ground) than in the other areas.
So, now I’m here scratching my head. What was it that caused the transformation? I’ve discussed this with many people and it comes down to two items:
- Water retention: The compost / sand mixture acted as a mulch and kept the water in the soil longer.
- Nutrient Addition: I didn’t think compost could deposit nutrients very quickly, but a friend who spend their professional life working for the agriculture department suggested that the nitrogen in the chicken manure could have given the plants a boost.
Maybe I should try a controlled experiment and have marked sections of my lawn setup with areas such as a control section, chicken manure section, fine mulch section, etc.
Post your thoughts & comments on my gardening forum.