When my basil plants started flowering and going to seed this year, I wanted to find out if basil can reseed itself or if it is better to collect the seeds, so I did some research. I called a local plant nursery to find out and spoke to a gardener with 5 decades of gardening experience and asked about it.
Basil plants can reseed themselves and grow back next year if the conditions are right. However, the seeds can only withstand mild frost for short periods of time, so they won’t grow back in most parts of the world since it gets too cold in the winter.
You can do some things to increase the chances of basil plants reseeding themselves and growing back, which I will describe below, but the best way to be sure you can grow the same basil next season is to collect the seeds.
In this post, I explain what I learned from the very experienced gardener about increasing the chances that basil reseeds itself and the easiest way to collect basil seeds.
Will Basil Reseed Itself and Grow Back?
Most basil varieties are annuals, but some are perennials if they grow in the right climate. The annual basil varieties are planted in the spring and die in the late fall or the winter when the temperatures get below the freezing point.
Since most basil varieties are annuals, they have to be sown every year, but whether the plants will reseed themselves or you have to collect the seeds and sow them depends on where you live and how cold the winters get.
While basil plants are theoretically able to reseed themselves and grow back, it is unlikely to happen unless you live in an area that never experiences frost. Basil seeds can withstand mild frost for very brief periods of time, but anything more than that will kill them.
After a cold winter, many plants can grow back either by reseeding themselves or growing back from the roots. Unfortunately, neither the seeds nor roots from basil plants are very resistant to cold weather, so if they are exposed to anything colder than a few degrees below frost for an extended period of time, they will not grow back.
The expert gardener I spoke to when I wanted to learn about if and how basil can reseed itself told me the following:
Sure basil can reseed itself, but it requires very good conditions. I have been growing basil for decades and never seen it happen, but in areas that are warmer in the winter, it is not uncommon.Arne, gardener with over 50 years of experience
As he said, if you live in an area where you don’t experience frost or, at most, extremely mild frost, your basil plants are likely (but not guaranteed) to reseed themselves, but for the rest of us that live in areas where we do get frost, they won’t, and our best option is to collect the seeds.
There is actually a good handful of perennial basil plants that will keep growing for multiple years even after producing seeds. Like any other basil plants, they can’t survive if they are exposed to frost, though. I explain more about this in the article on this link, where I also share a way to keep perennial basil plants alive through the winter even if there is frost.
While it is unlikely that basil reseeds itself if you live in an area that experiences frost in the winter, there is something you can do to make it come back. I will get into that now.
How to Make Sure Basil Grows Back Next Year
While basil can reseed itself and grow back, it is unlikely in areas that experience any frost. Still, the expert gardener I spoke to told me about a way to increase the chances.
Arne, the expert gardener, told me that a way to increase the chances of basil reseeding itself is to grow it inside a greenhouse as the temperature inside greenhouses generally doesn’t get as low as outside. However, in areas with multiple months of night frost in the winter, this likely won’t work.
Since basil can only reseed itself and grow back in warm climates, the best way to ensure your basil harvest for the next year (even if you live in a warm climate) is to collect the seeds from your plants. I have another article on this link, where I explain how to do that as well as how to store the seeds.
Read My Complete Guide to Growing and Caring for Basil
I have written a thorough guide where I cover all parts of growing your own basil including choosing a variety, sowing the seeds, the best growing conditions, pruning, propagation, harvesting, storing, solving various problems, and a lot more. You can find the article on this link.