The Vegetable Garden in September

The Vegetable Garden in September

  • By Ralph Morini
  • /
  • September 2019-Vol.5, No.9

The arrival of September signals the vegetable gardener’s opportunity to urge surviving summer crops toward their final production while planting cool weather leaf and root crops for a late fall and early winter harvest.

Whether or not you are planting fall crops, it is a good time to perform garden hygiene, removing spent and diseased plants. Diseased material should be burned or bagged and removed, not composted. A thorough cleanup now will reduce pest problems next spring.

It is also a good time to plant cover crops in unused garden space. Cover crops bring several benefits including reduced erosion and soil compaction, weed suppression, adding organic matter, and in the case of legumes, fixing atmospheric nitrogen for plant use. There are a couple of basic choices in terms of types of crops: winter-killed and winter-hardy.

  • Winter-killed cover crops die out after a few hard frosts, but their root and surface biomass help hold the soil and they are easy to till under in spring. Oats, field peas, oilseed radishes and rapeseeds are commonly used types.
  • Winter-hardy cover crops can either grow through or go dormant in winter but resume growth in spring. They should be cut prior to going to seed, with the roots being tilled under and greens used as compost or mulch. Allow 2 or 3 weeks after tilling for decomposition to start prior to planting. Winter-hardy choices include winter rye, winter wheat, hairy vetch, Austrian winter peas and crimson clover.

More information on cover crops can be found in earlier Garden Shed articles including Cover Crops from September 2015 and Minimum Till Cultivation from the February 2019 issues.


Although we all get a bit worn down by the heat and work involved in keeping the garden going all summer, it is worthwhile to summon one last burst of energy to do some fall planting. With an average first frost date of October 19-29 for the Piedmont region, September provides enough time for many spring cool weather crops to mature before the harsher winter weather arrives. The VA Cooperative Extension Vegetable Planting Guide  provides a lot of information. In a nutshell, possibilities for planting in early September include beets, endive, kale, collards, lettuces, mustard, radishes, spinach and turnips. The last six items should be ok if planted up through the end of the month. If you haven’t done much fall gardening, you should give it a try. It is very satisfying to continue the harvest into early winter, and many of the mid-summer pest and disease problems are reduced (weeds excepted of course), especially after the first frost.

Here is some further guidance for a strong finish to the gardening season:

Plant garlic in our area during the month of October. Remember, many retailers quickly exhaust their inventories of the most popular varieties before October. If you haven’t purchased garlic for fall planting, now is the time to do it. A few garden centers in our area sell garlic bulbs for fall planting, but the varieties are somewhat limited. However, there are many varieties and sources available on the web. For additional information, check out the article on growing great garlic in the October 2015 issue of Garden Shed.

Give your tomato plants one last feeding. Compost tea or fish emulsion should give them the extra energy they need to make that final push at the end of the season. Pinching off small green tomatoes and any new flowers will channel the plant’s energy into ripening the remaining full-size fruit.

Collect herbs from your herb garden for freezing and drying. If you don’t have access to a dehydrator, herbs can be dried quickly in a microwave oven. Simply place the herbs between two paper towels and heat for a minute. Remove them from the oven, cool, then test to see if the leaves are crisp. If not, return them to the microwave for a few more seconds. Store in sealed jars in a dark place so they will keep their color and flavor.

Pot up chives, parsley, and other herbs, and bring them into the house to extend the growing season.

If you’ve been lax in your garden documentation this year, tour your own vegetable garden and make notes on this year’s varieties, successes, challenges and chores, so that you can learn for next year. Make a sketch showing the location of this year’s plants to be used next spring for rotating your crops, an important pest and disease management practice.

Continue to weed your garden to prevent the weeds from going to seed and germinating over the winter and spring.

Remove all two-year-old canes from raspberry and blackberry plants to reduce overwintering of disease. Fertilizers containing potassium, phosphorus and magnesium or calcium can be applied but do not cultivate or irrigate at this time of the year.

Keep the strawberry patch weed free. Every weed you pull will help making weeding easier next spring.

Fall weed control around fruit trees is crucial because weeds act as hosts to overwintering insects.

Thanks for joining us in The Garden Shed — hope to see you again next month!


“Gardening by Month–September,” Missouri Botanical Garden,

“Monthly Horticulture Tip Sheets — Herbs, September,” Va. Coop. Ext. Albemarle/Charlottesville,

“Monthly Horticulture Tip Sheets — Fruit and Nuts, September,” Va. Coop. Ext. Albemarle/Charlottesville,