Reader, Hopernch writes, "I have caliche soil. Like others who have non-fertile substrate, I must truck in all garden dirt, but the lawn soils I have tried (sandy loams) become hard and dry. Composts (mushroom, etc) are best to improve my caliche soil, but for the whole huge lawn area as well as the gardens, it is becoming costly."
"Do you have any long-term ideas for improving ground cursed with caliche soil?"
Here's the answer provided to Hopernch:
How to Improve Caliche Soil
This problem is common in desert areas, meaning denizens of the Southwest in U.S. frequently encounter it. The calcium carbonate in the ground fuses soil particles together. Instead of a nice, friable ground, you end up trying to plant in dirt that is impenetrable in places.
You seem to be aware of the challenges that you face with caliche soils. Such ground presents a difficult set of circumstances in trying to grow a lawn. Common problems with caliche soils include the facts that they can create an impermeable layer that can prevent water from draining properly through the profile, that they can foster an accumulation of salts in the profile, that they can limit root depth, that they contain a high (that is, overly alkaline) soil pH, that they prevent nutrient uptake, etc. All of these issues may not be easily solved and can cause significant issues when trying to grow healthy lawn grass.
Lawn grasses typically will grow well in a soil pH range of 6-7.5. Caliche soil can create unfavorable pH for lawn grass growth. The quality of caliche soils can vary widely, so you may want to send samples into your local county extension and have complete soil tests done to determine your specific soil conditions and determine the best plan forward.
You're on the right track with your approach to amending the soil. Proper soil amendment is often necessary to create a suitable soil medium for turfgrass growth. Understandably, as you note, it may be impractical to amend the soil over the entire yard. There are some alternatives to look into here to reduce costs. Check with your town and surrounding towns; some public works departments offer free compost. You could also consider bringing in the materials needed to make your own compost, rather than buying costly, pre-made compost. For example, you can make an arrangement with certain restaurants to haul away a portion of their garbage; what's useless to them would be a coup for your compost bin.
While no lawn grass will grow well in caliche conditions without proper soil amendment, it has been suggested that buffalograss may have a higher tolerance for these conditions and may be a good alternative, depending on your location. If your preference is for bluegrass, tall fescue, or Bermudagrass, then 12-18 inches of soil amendment may be required. The soil test will provide you with good information to aid your decisions. No matter what species you select, proper maintenance will be paramount since growing conditions will not be ideal.
First and foremost, your situation will probably require an automatic irrigation system.
Source: the lawn care experts at John Deere.
Alternatives to Growing Lawn Grass
Hopernch mentions the desirability of improving the caliche soil with compost, while also acknowledging how hard it is to bring in enough compost to cover a space sufficient for growing a large lawn. There's a partial solution to this problem, but it means making the following compromise:
- You'll still be able to grow something in this space....
- It just won't be lawn grass.
Yes, I'm talking about growing xeriscaping plants. True, this solution does not furnish you with the lawn that you initially wanted. But there are two advantages in installing individual plants in this case, as opposed to a lawn:
- You can "pocket plant," meaning that you'll require less compost. That is, instead of improving the soil across the entire space, you need to upgrade it only in the individual planting holes for the plants that you're using.
- If you live in a desert area, you're fighting nature in your attempts at growing a lawn, due to the lack of water available. By growing, instead, plants that don't require much water, such as many cacti and succulents, you're making your life easier.