University of Vermont Extension 
Department of Plant and Soil Science

 Fall News Article 

SOWING WILDFLOWERS AND OTHER SEPTEMBER GARDENING TIPS

By Dr. Leonard Perry, Extension Professor

Dr. Vern Grubinger, Extension Associate Professor
University of Vermont
 

By September, your garden has probably gone the way of summer vacation--over for another year. While it's true that most of the crops have been harvested and the chores are winding down, it's not quite time to take that much-deserved break from gardening.

In the vegetable garden, pull up bygone or heavily diseased plantings, and take down pea trellises and bean poles. Once tomatoes are frosted, remove stakes, brush off soil thoroughly, and store in a dry place. next year, dipping stakes in a weak bleach solution can help avoid diseases such as bacterial canker.

Continue to remove weeds, especially mature ones that have been hiding under the foliage of crop plants. By keeping weeds from going to seed you can limit weed pressure next year. Harvest onions that have sized up and fallen over. If they are still upright as harvest time is approaching, pull the onions up or gently lift them with a spade.

For longest storage, it's important to allow the necks to dry down by letting them cure (dry) in a warm area until the outer leaves or scales are bright and the necks are completely dry. This will take a week to 10 days. Then store in a very dark and cool place (ideally 34 degrees F) for winter use.

After you have removed all plants and vines that have stopped producing, till the ground to incorporate roots and remaining residues, speeding their decomposition. If a soil test indicates the need for lime, you can add it before tilling. Then, it's a good time to plant a fall cover crop. This will protect tilled soil from erosion and add organic matter to improve soil structure. Oats are great because they grow quickly and will die over the winter, making them easy to deal with next spring.

Winter rye can be sown the latest, up until early October in most locations. Next spring it will continue to grow and improve the soil. However, it can be hard to get rid of if not incorporated thoroughly when it's small. If you don't sow a cover crop, apply a layer of leaves or clean straw to bare soil to reduce the damage that winter can do to exposed land.

September also is the time to prepare for planting fall crops such as garlic, which should be set in the ground around mid-October. For best results, order your garlic 'seed' from a local garlic farm, or get some at the farmer's market. Work up the soil with applications of compost and additional nutrients as recommended by soil testing.

Have your soil tested for other crops to be grown next year. You can pick up a soil testing kit from your local University of Vermont Extension office.

Listen to the daily weather forecast, especially if you live in an area that's prone to early killing frosts. It's a good idea to have some old blankets, burlap, plastic, or floating row covers handy in case frost or low overnight temperatures are predicted. These can be used to cover tomatoes, peppers, salad crops, and winter squash to protect them from chilling injury. Don't worry about your Brussels sprouts or kale. Their flavor actually will improve with frost.

You can leave root crops, including carrots, turnips, beets, potatoes, and parsnips, in the ground for harvesting later this fall and into early winter. Be sure to protect them from freezing by covering with a thick layer of straw. Mark the rows so you will be able to find your plantings once the snow falls.

The typically cool, wet September weather is ideal for sowing seeds for next year's wildflowers. Native species generally have a higher germination and survival rate, which is important in establishing wildflowers. You also should try to select species that are well suited to the soil pH, soil type, climate, and rainfall of your area.

Broadcast seed uniformly over a prepared seedbed, cover with a thin layer of straw, and firmly "push" seeds into the ground using a lawn roller for a large area, your hand or a board for smaller sections. Water gently. Do not fertilize.

Want to add a little fall color to your landscape? Hardy mums, available in a range of colors from rust to gold, are the answer. Pick a sunny site with good drainage. Prepare the planting hole about twice the diameter of the plant's pot. Dig and loosen the soil to a depth of eight to ten inches, mixing in lots of well-rotted manure or compost.

Hardy mums generally don't overwinter well although some gardeners have had success in getting their plants to bloom a second year. The trick seems to be planting in well-drained soil, cutting back the stems to ground level after bloom, and mulching generously in late October.

Early fall is the time to divide bearded irises, peonies, and daylilies. In late September, separate overcrowded lily-of-the-valley bulbs, and replant individually. Dig up corms of gladioli, dahlias, and cannas. Allow to dry completely, then store in a cool, dry location for replanting next season.

Other activities for September: pick apples for eating, applesauce, and pies; take cuttings of geraniums and begonias to root as indoor plants; plant tulips and other spring-flowering bulbs.


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