I found a thick green carpet of fuzzy seedlings in the damp back corner of my Mid-Atlantic garden one April. All of it came from a single borage plant the year before. I had left a few of its blue flowers to ripen on purpose. Every seedling grew from seed that dropped right there. None of it came from roots creeping under the soil.
So borage is not invasive in the strict sense. It is a vigorous self-seeding annual, and borage self-seeding is the only real reason anyone calls it pushy. The plant spreads by dropping seed, not by sending out runners. It stays where you let the seed fall, so you decide how far it goes. That makes borage self-seeding simple to live with once you understand it.
You may wonder is borage a weed, and the honest answer is no. A weed grows where you do not want it, and borage volunteers are easy to pull or leave as you choose. The plant is not on any state or federal noxious-weed list, which is the legal bar for a truly invasive species. Most extension offices describe it as a herb that reseeds readily, and that is the whole story. You will not find dire warnings about it the way you do for purple loosestrife or kudzu.
Here is how the spread works so you know what to expect. As each blue flower fades, it forms a small pod that splits and drops up to four hard seeds onto the ground below. One healthy plant can drop hundreds of seeds in a single summer. Those seeds sit through winter and sprout fast once the soil warms. That timing is why borage spreading looks so dramatic the next spring, even though you only grew one plant.
The key point is that this is a seed issue, not a root issue. Mint and ground ivy take over because their roots run sideways and pop up new shoots everywhere. Borage has a single taproot and stays in one clump. Pull that clump and it is gone for good. The plant cannot move on its own, so you stay in charge of where it grows. You will never find it three beds over by surprise.
That means your whole job is to manage volunteers. You are not fighting a takeover. Volunteers are simple to handle once you know the timing. The seed is your only lever, so cut it off before it ripens. Do that and you control the plant for the whole season.
- Deadhead: Snip spent flowers before they form seed pods. A plant that never sets seed cannot reseed, so this one habit stops next year's carpet.
- Pull early: Yank unwanted seedlings while they are small and the taproot is short. A two-inch seedling lifts out with one tug after a rain.
- Contain it: Grow borage in one bed or a large pot if you want to limit volunteers. Seed mostly falls close to the parent, so a defined spot keeps the spread tight.
To control borage seedlings through the season, walk the bed every couple of weeks in spring and hoe off the fresh sprouts before they get knee-high. Young plants give up without a fight. If you wait until they flower, you are back to deadheading every bloom to stop the next round.
I now leave one borage plant near my tomatoes for the bees and pull the rest as they appear. The flowers feed pollinators all summer and the young leaves taste like cucumber. Borage earns its place, and a five-minute walk through the bed keeps it from ever feeling like a problem.
Read the full article: Borage Plant: Grow, Eat & Use It Safely
