Rows Of Large Bright Yellow Sunflowers In A Field
(Image credit: William Krumpelman)

Many people have been drawn to images of bright yellow nodding heads growing side by side in wide sunflowers fields. Some people may decide to grow sunflowers so they can harvest the seeds, or others just like the happy sight of growing sunflower fields. Whatever your reason for growing sunflower fields, you will find out very quickly that there is one detail that you need to pay attention to. This is weed control in sunflowers. Due to the fact that sunflowers grown from seeds can take up to two weeks to appear, weeds can very easily establish themselves and then shade the sunflower seedlings, which will stunt the sunflowers' growth. You have three major options with weed control in sunflowers. You can either till or hoe between the rows, you can use chemicals, or you can use a Clearfield sunflower variety in combination with specific chemicals.

Tilling Weeds in Sunflowers

Tilling between rows is a good option due to the fact that sunflowers can stand up well to mechanical methods of tilling. For ideal weed control in sunflowers using the tilling method, till once before the seedlings come up out of the ground, about one week after they are planted. Then till one to three more times after the seedling have emerged but before they are tall enough to shade the weeds out on their own. Once the sunflowers have fully established themselves, you can do spot hoeing or flame scorching.

Weed Killers Safe for Sunflowers

Another option for weed control in sunflowers is using weed killers safe for sunflowers, or pre-emergents that will not affect sunflower seeds. When using chemicals for weed control in sunflowers, you must be careful to use very specific types of chemicals that will not harm the sunflowers. Unfortunately, many weed killers safe for sunflowers will only kill certain varieties of weeds, or can linger in food crop foods.

Clearfield Sunflower Varieties

For commercial sunflower production levels, you may want to consider purchasing a Clearfield sunflower variety. These are varieties that have been combined with a trait found in wild varieties of sunflowers that makes the sunflowers resistant to ALS-inhibitor weed killers. Clearfield sunflower varieties must be used in conjunction with Beyond herbicides for weed control in sunflowers.

Heather Rhoades
Founder of Gardening Know How

Heather Rhoades founded Gardening Know How in 2007. She holds degrees from Cleveland State University and Northern Kentucky University. She is an avid gardener with a passion for community, and is a recipient of the Master Gardeners of Ohio Lifetime Achievement Award.