Best Fertilizers for St Augustine Grass in 2026 [Expert Lawn Care Picks]

SeedRanch’s 24-2-11 formula stands out for its high nitrogen content paired with 6% iron, which really helps in producing that rich, deep green color St Augustine lawns crave. It covers up to 12,000 square feet, making it a great choice for larger yards.

I found that this fertilizer delivers nutrients consistently and the iron addition noticeably enhances the greening effect much faster than some competitors. It’s perfect for those who want a robust lawn without the hassle of multiple applications throughout the season.

Compared to other fertilizers with lower nitrogen or iron content, this one gave my lawn a thicker, healthier feel, especially during the peak growing months.

This Fertilome product doubles as a fertilizer and a weed killer, which is a huge bonus if you’re dealing with pesky weeds alongside lawn care. The 15-0-4 nutrient mix is designed specifically for St Augustine and similar grasses, providing a decent balance without overloading phosphorus.

What I appreciated was how it served as both a pre-emergent and post-emergent herbicide, reducing weed pressure early in the season and maintaining lawn health. It’s a solid choice for early spring application to get ahead of weed problems.

Compared to pure fertilizers, this one saves time and effort by combining feeding and weed control, though I’d recommend it only if you specifically need weed management.

Sunniland’s slow release nitrogen formula is a smart pick if you prefer steady feeding over time. The 20-0-6 nutrient ratio keeps your lawn fed without the spikes that can sometimes stress grass.

I liked that this fertilizer is phosphorus-free, which is ideal for areas where phosphorus runoff is a concern. The slow-release aspect means fewer applications and more consistent growth, which is perfect for busy gardeners.

Using this alongside a weed control product could be the best of both worlds. In my experience, it kept the lawn consistently healthy and green without pushing too much nitrogen at once.

Liquid fertilizers like this one from TPS Nutrients offer quick nutrient absorption, which means you can see results faster. It’s particularly good for boosting deep green color and encouraging new runners for thicker turf.

I’ve used liquid fertilizer when my lawn needed a quick health boost, especially during hot spells when St Augustine grass can struggle. It’s easy to apply with a sprayer and tends to give a noticeable lift in vibrancy within days.

While dry fertilizers feed over time, the liquid option is great for targeted treatments or when you want rapid improvement in lawn appearance.

This liquid fertilizer by Simple Lawn Solutions offers a great balance of nitrogen, phosphorus, and potassium, plus added seaweed and fish emulsion for organic nourishment. It’s designed to work well on various grass types, including St Augustine.

I found it especially useful for lawns that need both growth and root development support. The seaweed and fish ingredients add that extra boost for soil health that synthetic fertilizers sometimes lack.

Compared to pure synthetic options, this felt gentler on my lawn with steady improvements in both color and density over several weeks.

Scotts has long been a go-to for lawn care, and this Southern Lawn Food formula is designed with warm-season grasses like St Augustine in mind. It promotes strong roots to help your lawn withstand heat and drought.

I appreciated the ease of application and the fact that it’s pesticide-free, making it safe for people and pets right after use. It’s a reliable fertilizer if you want steady growth and resilience.

While it doesn’t include weed control, pairing it with a weed treatment can make your lawn care routine simpler and more effective.

This BioAdvanced product is a solid option if you want to tackle weeds and feed your lawn simultaneously. It targets broadleaf weeds common in Southern lawns and provides nutrients to promote thick, healthy grass.

I found it effective for preventing new weeds for up to six months, which is convenient if you prefer fewer applications. The granular form spreads evenly and feeds your lawn for about three months.

Compared to separate weed control and fertilizer products, this 3-in-1 approach saves time, though if your lawn is heavily infested, additional treatments might be necessary.