What to do in the Garden in September

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In the garden in September in Oklahoma, we have a second wind of growing. The temps are cooler, and tomatoes, peppers, and others start to produce again. This month-by-month garden planting guide will help you know what you can plant any time of year.

In September, it’s time to prune your tomatoes, peppers, and tomatillos so whatever fruit is on them will mature. If you leave the plants still growing and flowering, they won’t have time to ripen the fruit that results, but the fruit you already have will have less chance of maturing as well. To prune, just cut the flowers off everywhere you see them and the stems they are on as well.

In September, it’s time to pull all the plants that are disease or bug-infested or have died in the heat and clean out the gardens that are done. It’s also time to add compost to each garden and top the beds off with mulch to protect the microorganisms and beneficial bacteria and bugs from the weather.

If you leave your beds covered throughout the winter, you will have less moisture evaporating and less erosion of your soil. Another option is to plant cover crops in your beds for winter.

Gardens in September

It’s almost time to harvest sweet potatoes, some have flowered and are ready, and some have not yet flowered so we will wait until it’s about to freeze to harvest them. If you have sweet potatoes planted, keep an eye on the weather for the best time to harvest. When the greens freeze, harvest them immediately. If you don’t get a freeze, the longer you wait, the more pounds of sweet potatoes you will get, so wait if you can.

Our okra plants are still producing prolifically, so we will leave them until they stop. They will produce in the garden in September and far longer. You can make selections in your garden based on what’s still producing and what you want to keep tending.

If you haven’t planted seedlings for your fall crops, you still have a little time left to plant them. Broccoli, cauliflower, lettuce, carrots, peas, radishes, Brussels sprouts, kale, spinach, and other fall things can still be planted in Oklahoma, but hurry, the window of opportunity is almost gone.

What to plant in September in Oklahoma

There is a type of lettuce called Mache that you can plant now that should grow all winter long in your garden providing you with some greens. Last year, Brussels sprouts and kale also wintered over in our garden and continued to grow.

You can plant garlic at the end of September or beginning of October, whichever you prefer. I like to wait until October to have the kids plant ours. We will be planting around the 15. 

You also may be having a ton of excess produce coming from your end of summer garden. If you need ideas to use up excess cucumbers, okra, tomatoes, and more, check out the highlighted text.

What do you still have growing in your garden in September?

For what to do in the garden each month, click here. 

• What to do in the garden in January and February
• What to do in the garden in March
• What to do in the garden in April
• What to do in the garden in May
• What to do in the garden in June
• What to do in the garden in July
• What to do in the garden in August
• What to do in the garden in October
• What to do in the garden in November
• What to do in the garden in December