Spring has sprung and so have the weeds. Given the variety of weeds prevalent in the landscape there are numerous options for prevention and control. Choosing the most effective method depends on a number of factors including personal preference.
Cultivation is an effective and commonly used method of weed removal. It requires physically turning the soil to uproot weeds. Cultivation can be done mechanically with a tractor or walk-behind rototiller or with manual effort using long or short handled tools such as a garden hoe or hand-held cultivator. Though cost-effective, cultivation must be done regularly as the weeds will sprout again in the areas overturned. Using heavy equipment can break down the soil structure and cause compaction. It also requires care when cultivating planter beds to avoid damaging root systems of desired plants. Manual cultivation can also be very time consuming and is only recommended for small-scale gardens.
Mowing may be a useful weed control method for fields or paths between garden rows. Regular mowing can prevent the weeds from developing seed heads and spreading. A mowed pathway can prevent soil erosion. On the contrary, mowing is not an option for landscape planters as it risks damage to established gardens.
A two- to four-inch layer of mulch laid over a weed barrier such as weed fabric or even cardboard can be an effective preventative measure against weeds. Organic mulches such as wood chips can present a finished look to a landscape while also blocking out seasonal weeds. However, from one year to the next weed seeds may develop in the mulch layer. Additionally, organic mulches will decompose and become less effective at weed prevention so a new layer of mulch each year may be necessary. This method can be costly depending on the source of mulch.
Hand pulling is a method of weed abatement with which every gardener is familiar. Due to time and physical demands, hand pulling is recommended on a small scale such as container plantings and raised beds.
Herbicides can be used to control and prevent weeds but require careful attention to instructions to avoid causing more harm than good. Pre-emergent herbicides are applied to the bare soil to prevent weed seeds from germinating. Post-emergent herbicides are used to kill established weeds. Within this category are even more options. Contact sprays kill the plant parts with which the chemical comes in contact. Translocated sprays move through the plant after making contact and are more effective at killing perennial weeds. Selective herbicides are designed to kill specific types of weeds such as broad-leaf, while non-selective sprays will cause harm and potentially death to any plant. Using chemicals responsibly requires an understanding of the types of weeds you’re attempting to control and familiarity with each chemical’s capabilities. Closely follow the chemical instructions to avoid harming yourself, others and unintended landscapes.
As long as there are gardens there will be weeds. Preventing weeds by starting with a weed free medium and properly composting organic matter will pay off, but will not eradicate the problem entirely. Gardeners should be prepared to implement their weed management practices. Different methods may be used for various places in the garden so understanding the pros and cons of each will help you make an informed decision.
Cynthia Domenghini is an instructor and coordinator for K-State’s horticultural therapy online certificate program.