Many who move to the South mistakenly believe that St. Augustine lawns can be installed the same way that their northern bluegrass or fescue lawns were installed. They wonder where to buy St. Augustine grass seed and assume they can purchase it in order to establish a new lawn or fill in bare spots. This is an understandable mistake by someone who does not understand the difference between warm and cool season grasses. While there are some warm season grasses that can be propagated via seed (all centipedes, some bermuda grasses, and some zoysia grasses), St. Augustine is not one of them. St. Augustine grass can only be installed in a vegetative fashion: either by laying sod or planting grass plugs.
Pictured above: CitraBlue® St. Augustine plugs.
Can you buy St. Augustine seed?
There are several advantages and disadvantages to each propagation method (vegetative sod or plugs vs. seed) that this blog post will not address. Instead, this blog will address the fact that there is not a seed option for St. Augustine grass when establishing a lawn. You can read more about the differences between various methods of installation in the Sod University article on When to Use Sod, Plugs or Seed.
St. Augustine grasses do not produce enough viable seed for commercialization. For this reason, seed is not produced for lawn propagation use and it is therefore not available for sale at your local garden center.
Sod farms propagate St. Augustine grass vegetatively, as they do most warm season grasses. Sod farms cultivate new St. Augustine sod fields by planting small plantlets (plugs/sprigs) of St. Augustine grass, which grow into a full field of sod in 8–12 months depending on the latitude of the sod farm. Take a look at the video below to see the process of how farmers sprig warm season grasses using slabs of sod.
Once the sod is harvested, the sod farmers leave ribbons of grass in the field, which then re-grow into a full field of sod in a little less time than the original field grew in.
With that being said, there’s no such thing as St. Augustine seed including Palmetto St. Augustine seed, CitraBlue St. Augustine seed and Floratam St. Augustine seed. A grass plug is an individual turf plant that is grown in a tray; their size can vary, but generally an individual plug measures anywhere between 1.5–3 inches in length/width. Planted from 9–12 inches apart, they will continue to spread and fill in over time, creating a solid ground cover of your preferred grass type.
If you are interested in plugs as a cheaper alternative to installing sod, learn more about grass plugs in the Sod University article, What are Grass Plugs and When to Use Them. Another article you may find of interest discussing how to grow st. augustine grass.