Timing matters as much as the product itself. Apply the right MicroLife formula at the wrong time of year and you waste it — or worse, you push growth right before a freeze. Here’s exactly what to do each month, and why, for St. Augustine, Bermuda, and Zoysia lawns in the Houston area.
The Two Rules Behind This Whole Calendar
- Only fertilize actively growing grass. Soil temperature needs to be consistently above 65°F. Feed dormant grass and you’re just feeding winter weeds instead.
- Stop all nitrogen by the end of August. Late nitrogen pushes soft new growth right before Houston’s first real cold snaps, and that new growth is what gets damaged first.
Everything below follows from those two rules.
January – February: Do Nothing
Your lawn is dormant or close to it. This is the one time of year we tell people not to buy fertilizer — save it. If you’re itching to do something productive, this is a good window for soil testing so you know your starting pH before spring.
March: First Feeding of the Year
Once you’ve mowed the lawn twice as it wakes up, it’s time for the first application. Use MicroLife Multi-Purpose 6-2-4 — it works across all three grass types and gets the season started without overloading a lawn that’s just coming out of dormancy. Apply 15–20 lbs per 1,000 sq ft.
If last year’s soil test (or last year’s yellowing) told you your pH is a problem, March is also a fine time to start with MicroLife Acidifier 6-2-4 instead — see our guide to picking the right MicroLife formula if you’re not sure which one applies to you.
April: Watch, Don’t Feed Yet
Most Houston lawns don’t need a second application this early — one feeding in March typically carries a lawn 6–8 weeks. Use April to watch for chinch bugs starting to wake up in St. Augustine, especially in sunny spots near driveways and sidewalks, and to keep mowing at the correct height for your grass type (see our mowing height reference guide).
May – June: Second Feeding, Grass-Type Specific
This is where the schedule splits by grass type:
- Bermuda lawns: Switch to MicroLife Hybrid 20-0-5. Bermuda is an aggressive grower and can use the extra nitrogen for faster, denser growth. Apply 5–7 lbs per 1,000 sq ft.
- St. Augustine and Zoysia lawns: Stay on MicroLife Multi-Purpose 6-2-4 at 15–20 lbs per 1,000 sq ft. Zoysia especially doesn’t want more nitrogen than this — over-fertilizing Zoysia causes thatch buildup and increases disease risk.
Throughout Summer: Watch for Yellowing
If grass yellows despite a normal watering and fertilizing routine, it’s usually iron chlorosis from Houston’s alkaline soil, not a nitrogen problem. MicroLife Acidifier 6-2-4 (15–20 lbs per 1,000 sq ft) is the fix — it lowers soil pH with 12% sulfur so the iron already in your soil actually becomes available to the grass. This can be applied any time yellowing shows up, not just on the calendar schedule.
Summer is also chinch bug and armyworm season — armyworms in particular can strip a Bermuda or Zoysia lawn in 48–72 hours, so if you notice fast-spreading damage, treat it immediately rather than waiting for your next scheduled feeding.
August: Last Nitrogen Application
Repeat the May–June application one more time — Hybrid for Bermuda, Multi-Purpose for St. Augustine and Zoysia — and then stop nitrogen for the year after this. This is a hard cutoff, not a suggestion: anything applied after August pushes tender growth into fall that a cold snap can kill.
September: Disease Prevention, Not Growth
This is the most important month on the calendar if you’ve ever had brown patch or large patch. Apply MicroLife Brown Patch 5-1-3 preventively for St. Augustine and Zoysia lawns — 15–20 lbs per 1,000 sq ft — before symptoms show up, not after. Houston’s September pattern of warm, humid soil and cooling nights is exactly what triggers these fungal diseases every year. Brown Patch 5-1-3 also functions as a complete fertilizer, so this month’s application isn’t wasted even in a year where disease doesn’t show up.
October – November: Soil Health, Not Growth
Shift focus entirely to the soil. MicroLife Humates Plus 0-0-4 (10–20 lbs per 1,000 sq ft) is a concentrated soil conditioner that loosens Houston’s gumbo clay better than gypsum, builds root systems, and helps your lawn hold water more efficiently heading into winter. This is also a good window to aerate if your soil is compacted — Humates Plus works even better on aerated soil.
December: Do Nothing (Again)
Back to dormancy. No fertilizer needed until March.
Full Calendar at a Glance
| Month | Action | Product |
|---|---|---|
| Jan–Feb | Nothing | — |
| March | First feeding | Multi-Purpose 6-2-4 |
| April | Watch only | — |
| May–June | Second feeding | Hybrid (Bermuda) / Multi-Purpose (St. Aug, Zoysia) |
| Summer | As needed for yellowing | Acidifier 6-2-4 |
| August | Final nitrogen feeding | Hybrid (Bermuda) / Multi-Purpose (St. Aug, Zoysia) |
| September | Disease prevention | Brown Patch 5-1-3 |
| Oct–Nov | Soil health | Humates Plus 0-0-4 |
| December | Nothing | — |
Get Everything in One Trip
All five formulas are in stock at both our Magnolia and Tomball yards. If you’d rather not track the calendar yourself, call us in any given month and tell us what your lawn looks like — we’ll tell you what to grab. Browse the full MicroLife lineup, check the Lawn Care Guide for grass-specific detail, or get a free quote and we’ll add fertilizer to your next delivery. Call (281) 259-6375.