Weed Control
Weed control in outdoor garden mum production areas can be achieved in several ways.
Manual – Physically removing weeds by pulling, hoeing or cultivating.
Mulches – Gravel, salt hay, black plastic and woven plastic ground covers (weed mats) can all provide satisfactory weed control. The woven ground cover mats are especially well adapted for use in conjunction with tube watering systems.
Chemical – Devrinol, Pendulum, Ronstar, Treflan and XL are preemergence herbicides used to prevent weed growth in container and field-grown garden mums. They are ineffective on existing weeds. Do not use any of these herbicides inside a greenhouse.
One application is usually adequate if there are few weed seed sources. Following planting, another application can be made if needed. Overhead application to plants should be done when mum leaves are dry. After application, water overhead with ½" of water. Beds under containers must be well-drained to prevent herbicide accumulation under containers.
Postemergence – Herbicides such as Acclaim Extra, Envoy, Ornamec 170, Fusillade II and Vantage can be used to control certain grassy weeds, but they do not control broadleaf weeds.
Remember that both preemergence and postemergence herbicides only control certain weeds. Some grasses or broadleaf weeds may not be controlled. Read the label for weeds controlled and for use rates and application methods. Also keep in mind that damage can occur with drift or vaporization when using weed killers such as 2-4-D near growing plants.
Before using any of these pesticides and herbicides, be sure that they are registered for use in your state. Check with your local county extension agent or state university extension service. See label for use rate and application methods. Always follow label directions. The label is the law.