Warm-season grass
How to fertilize St. Augustinegrass
A coarse, wide-bladed warm-season grass, common along the Gulf Coast and in Florida, that tolerates more shade than most. Here is how much it needs, when to feed it, and a calculator already set up for it.
St. Augustinegrass at a glance
- Nitrogen a year2–4 lbper 1,000 sq ft
- Main feedingsMay–Augafter green-up
- Per feeding0.75 lb Nusual band 0.5–1 lb
- Feedings a year2–5at 0.75 lb each
Feeding calendar
When to feed St. Augustinegrass
Warm-season grass
2–4 lb of nitrogen per 1,000 sq ft a year
At 0.75 lb a feeding, that is about 2–5 feedings a year.
Main feedings: May, June, July and August. Light or regional feedings: April and September.
Start after the lawn has fully greened up in spring, feed through summer, and stop by early fall so the grass is not pushed into growth before cold weather. Florida's guide allows up to 6 lb a year in South Florida.
Typical ranges from university extension guides. Your state or county guide wins. See the sources.
Calculator
How much to spread on your St. Augustinegrass
It starts at 0.75 lb of nitrogen per 1,000 sq ft on a 5,000 sq ft lawn. Change the numbers to match your lawn and your bag.
Worked examples
One feeding on 5,000 sq ft of St. Augustinegrass
At 0.75 lb of nitrogen per 1,000 sq ft, with four common bag numbers.
| Bag numbers | Per 1,000 sq ft | For 5,000 sq ft |
|---|---|---|
| 29-0-4 | 2.6 lb | 12.9 lb |
| 16-4-8 | 4.7 lb | 23.4 lb |
| 10-10-10 | 7.5 lb | 37.5 lb |
| 46-0-0 | 1.6 lb | 8.2 lb |
Good to know
Feeding St. Augustinegrass well
Start after the lawn has fully greened up in spring, feed through summer, and stop by early fall so the grass is not pushed into growth before cold weather. Florida's guide allows up to 6 lb a year in South Florida.
Keep any single feeding to about 1 lb of quick-release nitrogen per 1,000 sq ft or less. Slow-release products may be labeled for more. Florida limits quick-release nitrogen to 0.7 lb per feeding.
The product label has the final say on rate and timing, and some states limit phosphorus or set dates when lawn fertilizer cannot go down. See how these numbers are worked out.
Questions
St. Augustinegrass, answered
How much nitrogen does St. Augustinegrass need a year?
Typical university guidance is 2–4 lb of nitrogen per 1,000 sq ft a year. Florida's guide allows up to 6 lb a year in South Florida.
When should I fertilize St. Augustinegrass?
The main feedings fall in May, June, July and August. Light or regional feedings: April and September. Start after spring green-up and stop by early fall.
How much fertilizer do I need for 5,000 sq ft of St. Augustinegrass?
At 0.75 lb of nitrogen per 1,000 sq ft, a 29-0-4 product needs 2.6 lb per 1,000 sq ft, so 12.9 lb for 5,000 sq ft in one feeding. Use the calculator on this page for your own lawn and bag.