How much lime your lawn needs, by weight and in bags, without a soil test. Enter your lawn size, your soil and what the lawn is doing to get a rate that's about right for most lawns.
About this tool: how much lime does a lawn need?Lawn Liming Steps
A soil test from your county Extension office (for a small fee) gives the real number. No test yet? This page estimates it from what the lawn shows: about 5.8 now, aiming for 6.2.
It spreads cleanly through a normal spreader. For this lawn: 6 bags, about 221 lb. Dolomitic also adds magnesium.
Mow first. Each pass gets half the rate: about 22 lb per 1,000 sq ft. Check the bag for your spreader's setting.
Walk the lawn one way, then again at a right angle. The crossing passes cover the stripes a single pass leaves.
Water lightly to wash it off the blades. Keep fertilizer off for two weeks. The pH moves over three to six months. One application is enough.
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Open the calculatorLime raises soil pH and adds calcium. Most lawn grasses grow best at 5.5 to 6.5 (UGA). If your pH is already fine, lime can only hurt.
Rain leaches out calcium and magnesium, and nitrogen fertilizer acidifies soil directly. Pine needles have little effect.
It depends on how far the pH needs to move and how strongly your soil resists the change. To raise it one full point:
| Soil type | Lime per 1,000 sq ft | Per m² |
|---|---|---|
| Sandy / light | 30 lb | 146 g |
| Sandy loam | 60 lb | 293 g |
| Loam (typical topsoil) | 80 lb | 391 g |
| Clay loam | 100 lb | 488 g |
| Heavy clay | 115 lb (Bizon estimate) | 561 g |
Iowa State and UC Extension (sources). Never more than 50 lb per 1,000 sq ft (244 g/m²) at once (Virginia Tech, NCDA). The calculator splits anything larger into passes six months apart, up to three. Past about 150 lb per 1,000 sq ft (732 g/m²) it stops splitting and asks for a soil test instead, because a correction that big depends on a starting pH this page can't measure.
This estimates your starting pH from what the lawn is showing. A lab measures reserve acidity, which sets the real requirement and can't be seen from the surface. Tests are cheap through US county Extension, or a local soil lab elsewhere. Too little lime means a second pass. Too much takes a year or more to undo.
It grows best at 5.0 to 6.0 and declines at the 6.0 to 6.5 that suits fescue. Soil test first.
This is the only number on the bag that changes how much you need. This tool assumes 95% calcitic and 105% dolomitic. If your bag prints something else, scale the answer by the figure assumed for the product you picked divided by your bag's. A 90% calcitic bag is 95 ÷ 90, about 6% more.
| Product | Typical CCE | Effect on the amount |
|---|---|---|
| Calcitic limestone (pelletized or pulverized) | 85 to 100% | Baseline |
| Dolomitic limestone | 95 to 109% | About 10% less by weight |
Two passes at right angles, half rate each, then water in. Wait two weeks before fertilizing. Fall is best, since pH takes three to six months to move.