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September Gardening Tips

Gardening Information

Finally some cool evening temperatures begin to trigger fruit to ripen, foliage to turn, flowers to re-bloom, and gardeners to get back in their gardens.

You can encourage blossoms by continuing to dead head (See July for more info).

Flowers have used up much of the nutrition in the soil and are ready to soak up anything you can give them. Geranium’ s and petunias in particular perk up after the heat by applying a tablespoon of Epsom salts sprinkled on top of the soil. Also much of the nitrogen that provides green coloring has been washed out of the soil with extra irrigation. Many trees and shrubs in particular need extra nitrogen and iron. Common deficiency symptoms are yellow leaves with dark veins. Apply a general purpose mix of quick release and slow release fertilizers either organic or synthetic. Liquid feeds that are sprayed directly on foliage can also help.

A great time to plant, roots continue to grow throughout the fall and early winter. This allows them to have an extensive root system before next seasons hot temperatures. This is a great time to go shopping for trees, shrubs and perennials. You can see what is still in bloom and has colorful fall leaves.

Check the root balls of recently purchased plants. If the roots are growing in a circular pattern following the outline of the pot, they are root bound. The roots should be cut and opened up to allow them to grow in new directions out into the surrounding soil. Make an “X” shaped cut on the bottom of the root ball about an inch deep with a cut about halfway up each of the four sides.

A great time to redesign and move plants around, transplant deciduous shrubs and trees when they start to develop fall color. Perennials can be divided and transplanted. Older ornamental grasses can be revived by occasionally uprooting, dividing, and replanting. Division is done by uprooting the entire root ball with as much of it intact as possible. Place the root ball on a hard surface. Usually the center of the perennial or grass is dead resulting in a doughnut like plant. Look for natural splits in the ‘doughnut’ and begin teasing the roots apart into approximately six inch round hunks. If the roots are quite entangled, you can cut them apart into the new sections. Now you can replant or have extra plants to share. Shasta daisies, daylily’s, green fountain grass, and salvia all respond well to division every three to five years.

Order or buy spring bulbs and plant before the ground freezes. A general rule is to plant them twice as deep as the bulb is wide. Join us for a great selection of bulbs at our Fall Plant Sale. Garlic and shallots cloves should be planted several inches deep.

Stop deadheading roses letting colorful red rose hips form. Let other flowers go to seed producing colorful seed pods and winter browse for birds.

If your lawn has thick thatch (dead layer) or is compacted from heavy use or wet shade a fall core aeration can loosen and open up the soil. This will help water, nutrition, and air get into the root zone. This is also a wonderful time to reseed lawn areas that are thin or bare. Most lawns are Kentucky bluegrass varieties. More water-wise and heat tolerant dwarf tall fescues are a good choice for over seeding.

Check your sprinkler system and shorten the watering times of your lawn.

Your hard work is ready to pay off as you harvest and dry your herbs. Harvest them early in the day by cutting off entire stems. Wash everything well and place on screens, cookie sheets or trays and let them air dry for several days. When they are dry, strip the leaves off and store in air tight containers.

Apply a broadleaf weed killer on your lawn. Dandelions are perennial weeds that live from year to year. As the weather cools they begin to store food in their large tap root. They begin pulling nutritional resources from the leaves into the root, thus any chemical applied to the leaves will translocate into the roots. This provides a more complete kill than spring applications.

A second growing season of cool season vegetables is a great way to enjoy your fall. Lettuce, peas, radish, spinach, kale, and chard all perform well in this weather. You can begin to harvest onions, shallots and garlic for use and storage.

Want to learn about native plants for water conservation, perennial and herb care, or how to use stone in the landscape? Check out our monthly calendars for useful classes!