Basil plants need sunlight and warm weather to thrive and be productive, so when it starts to get darker and colder at the end of the season, you need to know what to do.
What you should do with your basil plants at the end of the season depends on a couple of things. Primarily on what basil variety you are growing and where you live, because while most basil varieties are grown as annuals, some can be grown as short-lived perennials that can live for several growing seasons if they grow in the right climate.
Where I live, basil can only grow as an annual plant so I always do the same things at the end of the season. You should most likely do the same things.
Unless you live somewhere that never gets frost, always has at least 6 hours of sunlight per day, and grow a perennial basil variety, you should do the same things as I do with your basil at the end of the season. Your plants won’t come back next year (read more about why here), so I’ll explain how to get the most out of them in this article.
If you do live somewhere like that, though, scroll a bit down as I explain what you should do later in this article.
First, let’s get into what to do with basil at the end of the season if you grow it as an annual plant.
3 Things You Should Do With Basil at the End of the Season
When it starts to get cold and there is less and less sunlight every day, your basil plants most likely have very limited time left, so there are a few things you should do to get the most out of them and to be ready for the next growing season.
1. Pick any green leaves that are left on your basil plants
The first thing you should do when your basil plants are starting to die back at the end of the season is to make sure you harvest the leaves that are left on them.
Unless you grow a perennial basil variety and live in the right climate (which I will get more into later in this article), your plants won’t come back, so make sure you don’t miss out on the last harvest.
You should be aware that the plants have most likely started producing seeds and the leaves might taste bitter when that happens, so make sure to taste them before you use them in cooking.
If you have more leaves than you can use after you are done picking the last ones from your plants, you should know how to preserve them and store them for later use. I share four easy ways to do that at the end of the article on this link.
2. Collect seeds from your basil flowers
Basil plants flower towards the end of the growing season. The purpose of flowering is to finish the plant’s reproductive cycle, which essentially means “to produce seeds”. After the plants are done flowering, you can collect the seeds and use them to grow a lot of new basil plants when the next growing season starts.
The easiest way I have found to collect basil seeds is to wait until the flowers turn brown and completely dry and then cut them off the plant. While holding onto the base of the flowers, place them in a bag or similar and shake them to make the seeds fall off into the bag. I have a full guide for you on this link.
You might not get all the seeds with that method, but it is an excellent way to get most of them very quickly and easily in my experience. If there are some seeds left in the flowers after doing this, you can just pick them out one by one with your fingers or some tweezers.
When your basil flowers look like mine in the photos in this article, they are almost done producing seeds but not quite yet. Wait for them to drop the flower petals and turn brown and dry out before you try to collect the seeds.
3. Pull the plant out of the ground or remove it from the pot
Once you have picked all the leaves from your basil and collected the seeds you want, there is nothing left to do except pull the plant out of the ground or remove it from the pot.
You can either plant something else in the spot you freed up (if it isn’t too late in the season) or just prepare it for next year by mixing some fresh, nutrient-rich soil or compost into the remaining soil and (ideally) covering it with some mulch.
You can leave the roots in the ground to be broken down and provide organic matter to the soil and you can compost the plants.
As I explained at the beginning of this article, some basil varieties can be grown as perennials if you live in the right climate. If that is your situation, keep reading as I explain what to do.
What to Do With Perennial Basil at the End of the Season
Some basil varieties can live for several years if they grow in the right climate. That means sunlight all year and temperatures that never dip below the freezing point. I go into more detail about when basil can and can’t survive winters in the article on this link.
If you grow a perennial basil variety in the right climate, the growing season technically lasts all year and what you should do is very different from what you have to do with annual varieties since you want to keep the plant growing and producing.
Instead of picking the remaining leaves and getting rid of the plant like with annual varieties, you should just keep the plant fresh and healthy by continuing to care for it and remove any dead growth when you see it. This includes frequent pruning, which is an important part of it. I have a guide for that here.
You can still collect seeds from your perennial basil plants at the end of the season and you can also still use the trick I use, which I explained above, where you cut off the flowers and shake them inside a bag to loosen the seeds.
Your perennial basil plants will eventually start flowering and while you can remove the flowers to delay the flowering and seeding stage a bit, it can be a great idea to let the plants flower.
Basil flowers attract a bunch of beneficial insects to your garden that can help pollinate your other plants, which makes them produce more fruit than they would otherwise.
Some popular examples of perennial basil varieties include:
- Greek basil
- Thai basil
- White perennial basil
- Pink perennial basil
- Holy basil
If you aren’t growing any of these already, I recommend doing so if you can where you live. Basil is a great plant for repelling pests in your garden and, as mentioned, the flowers attract a lot of beneficial insects. Especially the variety called Perennial basil since it has a very strong aroma. That’s the one in the photo above.
When Does the Basil Growing Season End?
The growing season for basil depends entirely on where you live, but I have a simple rule of thumb that can help you figure it out for your area.
The basil growing season begins in the spring about 2 weeks after the last frost and lasts until the first frost in the fall. Basil can be grown all year round in areas that never experience frost and get about 6 hours of sunlight or more per day.
I like to remove the flowers from my basil plants for some time to keep them growing and producing because once they flower, they will use most of their energy on that instead of growing. If you grow your basil for the leaves primarily, I recommend you do that too. You can read more about why on this link.
I also like to let the plants flower towards the end of the season, however. Basil flowers can attract a lot of beneficial insects to the garden that can help pollinate your other plants, which means bigger harvests for you.
If there is enough sunlight at the time (about 6 hours per day), you can start basil indoors about 4-6 weeks before the last frost to get a head start on the growing season.
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.