Florida pusley (\(Richardia\) \(scabra\)) is a tenacious, low-growing annual or perennial weed that invades lawns and landscape beds across warm climates. It belongs to the coffee family (Rubiaceae) and is also known as rough Mexican clover. The plant’s prolific seeding habit allows it to quickly establish dense mats, making eradication challenging. Successful management requires a two-pronged approach: eliminating existing plants and preventing the vast seed bank in the soil from sprouting. This article details the steps necessary to control current infestations and implement long-term prevention strategies.
Identifying Florida Pusley and Understanding Its Seed Cycle
Florida pusley is characterized by its prostrate, spreading growth pattern, which allows it to hug the ground and evade mowers. The stems and leaves are covered in fine hairs, and the leaves are oppositely arranged and egg-shaped to lance-shaped. Its most recognizable feature is the small, white, tubular flowers clustered at the tips of the stems, often giving the appearance of little white patches.
The plant’s lifecycle is dictated by rapid seed production, which can begin as early as March and continue through December in warm regions. Florida pusley spreads almost exclusively by seed, released in dried fruits called schizocarps that typically fall close to the parent plant. These seeds can germinate almost immediately, especially in bare or disturbed soil. Optimal germination occurs at soil temperatures ranging from 68°F to 95°F, and burial deeper than half a centimeter impedes sprouting.
Immediate Control Methods to Stop Current Seed Production
The first step in control is eliminating all currently growing plants before they contribute more seeds to the soil. For small, scattered infestations, hand-pulling is an effective mechanical method, provided the entire root system is removed. Since Florida pusley has a shallow taproot, it can often be pulled completely from moist soil. Any pulled plants showing flowers or seeds must be disposed of in a sealed bag, not in a compost pile, to prevent further seed dispersal.
For larger infestations, post-emergent herbicides are the most practical solution for eliminating established weeds. These chemical treatments are absorbed by the foliage and translocated throughout the plant, interfering with its growth hormones. Herbicides containing active ingredients such as 2,4-D and dicamba are effective selective treatments for Florida pusley in many turfgrasses, including Bermuda, Bahia, and Zoysia.
These compounds target broadleaf weeds without harming most turfgrasses. Application is most successful when the pusley plants are young and actively growing, as mature plants may require multiple treatments for complete control. Users must be cautious with application, especially in St. Augustinegrass or when temperatures exceed 85°F to 90°F, as this can increase the risk of damage to the desirable turf.
Long-Term Strategies for Preventing Seed Germination
Once existing plants are removed, the focus shifts to preventing dormant seeds from germinating using pre-emergent herbicides. These products create a chemical barrier at the soil surface that inhibits cell division in the emerging seedling’s root system, causing it to die before breaking ground. Timing is paramount, as the herbicide must be in place before the seeds sprout.
As Florida pusley is a summer annual weed, the pre-emergent application should occur in late winter or early spring, typically when daytime temperatures reach 65°F to 70°F for several consecutive days. Common active ingredients include oryzalin, benefin, and pendimethalin. A second application may be needed six to nine weeks later to provide season-long control.
Cultural practices also play a major role in prevention by making the environment unfavorable for seed germination. Maintaining a dense, healthy turfgrass stand is highly effective, as vigorous turf can outcompete the low-growing Florida pusley. This involves proper mowing, fertilization, and irrigation. In landscape beds, a thick layer of organic mulch (two to three inches deep) can physically block the light necessary for the seeds to germinate.