White clover (Trifolium repens) and its smaller cultivar, micro-clover, are increasingly common components of modern lawns. Before the 1950s, clover was an expected and desired part of standard grass seed mixtures. The widespread introduction of broadleaf herbicides following World War II effectively eliminated clover, leading to its perception as a weed. This historical view is now shifting as homeowners recognize the many benefits clover offers to the overall lawn ecosystem.
Ecological Contributions of Clover
Clover is a legume, possessing the ability to capture nitrogen from the air and convert it into a usable form for the soil. This process, known as nitrogen fixation, occurs through a symbiotic relationship with Rhizobium bacteria housed in nodules on the plant’s roots. The fixed nitrogen acts as a continuous, natural fertilizer, significantly reducing the need for synthetic nitrogen applications.
The deep root structure of clover provides superior resilience compared to traditional turf grasses. This extensive root system allows clover to access moisture deeper in the soil profile, making it highly drought-tolerant. During periods of heat or limited rainfall, a lawn mixed with clover will often maintain a greener color while pure turf grass may turn brown.
This dense, low-growing foliage naturally shades the soil, which helps to suppress the germination and growth of many unwanted broadleaf weeds. By outcompeting other plants, clover reduces the necessity of applying chemical herbicides. Furthermore, clover flowers are a valuable nectar source, attracting and supporting local pollinator populations like bees and butterflies.
Factors Determining Mowing Necessity
Mowing a clover-inclusive lawn depends entirely on a homeowner’s personal goals for the space. If the primary objective is a highly manicured, uniform appearance that blends seamlessly with surrounding turf grass, then regular mowing is necessary. Clover tends to grow slightly taller and develop a patchy, clumped look when left uncut.
Mowing is also a direct management tool for controlling the plant’s flowering cycle, which is a major consideration for families with children or high-traffic areas. While clover flowers are beneficial for pollinators, the resulting bee activity can be a safety concern, particularly for those who walk barefoot. Mowing the clover before or as the flowers begin to bloom can significantly reduce the number of bees attracted to the area.
If clover is only a portion of the lawn, mowing helps to prevent it from becoming overly dominant and crowding out the desired turf species. An unchecked spread can lead to a monoculture, so periodic cutting helps to maintain the proper balance between the clover and the existing grass. Cutting the lawn also serves to prevent the clover from going completely to seed, thus managing its overall proliferation and maintaining a tidier look. For those using micro-clover, which is a dwarf variety, mowing frequency can be greatly reduced due to its naturally smaller leaf size and less aggressive vertical growth.
Practical Guidelines for Mowing
When mowing a clover lawn, set the mower blade height to a high setting, ideally three inches or more. Cutting too low, which is referred to as scalping, can stress both the clover and the underlying grass, making them more susceptible to disease and heat damage. A higher cut encourages deeper root growth and helps the clover withstand environmental stress.
The frequency of mowing can be significantly less than a pure grass lawn, often only needing attention every four to six weeks. The best time to mow is when the clover reaches a height of about four inches or when flowers become abundant. Only removing the top one-third of the plant height in a single cut minimizes stress on the foliage.
It is recommended to leave the clippings on the lawn after mowing, a practice known as mulching. As the clover clippings decompose, they release the fixed nitrogen back into the soil, directly benefiting the surrounding grass. Avoid mowing during periods of extreme heat and drought.