How to Control Borage

Weeding and clipping are frontline defenses in keeping borage under control.

A patch of borage plants provides vivid blue, star-shaped flowers that brighten up salads, chilled summertime drinks and vegetable side dishes. Those charming, cucumber-flavored flowers, if left on the plant, produce large quantities of seed that turn into dozens, if not hundreds, of new little borage plants. Left unchecked, Borage officinalis can turn into a gardener's headache as it grows like a weed through vegetable and flower beds. Persistence and attention to timing keeps borage under control as a companion plant that deters tomato worms and attracts beneficial honeybees to your garden.

Things You'll Need

• Garden pruners
• Garden hoe
• Mulch
• Herbicide

Instructions

1. Plant borage at the edges of your garden beds rather than in the middle of a planting area where the seeds from mature flowers will quickly germinate in the rich soil. Grow borage in clusters of three or more plants in several small areas rather than interspersing the plants throughout your garden.

2. Pick borage blossoms daily during their flowering period, typically in June and July, to prevent any flowers from wilting, going to seed and scattering the seeds across the ground. If daily picking is not feasible for a period of time, clip maturing flower clusters off with garden pruners and discard to reduce seed dissemination during your absence.

3. Pull new borage plants that sprout up in existing garden rows by hand. Water the garden bed first so that you can grasp the borage leaves and gently lift them out of the soil without disturbing the other plants' roots. Scrape the ground between planted rows with a garden hoe to remove newly sprouted borage.

4. Spread a 4- to 6-inch layer of mulch over the ground immediately surrounding your borage plants to suppress seed germination and growth.

5. Treat an area where borage has become particularly invasive with herbicide if manual control measures are not effective. Consult your county extension agent or local garden center staff to identify a product safe for application in vegetable gardens. Apply the herbicide according to the manufacturer's label directions and wait the recommended time period before cultivating and planting the treated area.

References

• Penn State Vegetable Crop Resources: Borage
• Michigan State University Extension: Companion Planting
• Washington State University: Aggressive/Invasive Plants
• Maryland Cooperative Extension; Cultural and Chemical Control of Weeds in Home Vegetable Gardens; C. Edward Beste, et al.

Resources

• Reiman Gardens; Edible Flowers; Richard Jauron et al.