Maine Home Garden News, University of Maine Cooperative Extension

In this issue:
August is the month to . . .
Fall Cover Crops for Home Gardeners
Herbal Abundance: Harvesting and
Drying Herbs

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Maine Home Garden News
August 2009

August is the month to . . .

Check your garden each day for ripening vegetables. Harvest vegetables at their peak. Be Patient! Harvest maybe delayed by our cool, wet weather.
Make weekly observations of all garden plants for pest damage. This may mean getting on your hands and knees to inspect plants closely. Check leaves, stems, flowers, and fruit for damage, eggs, etc.
If a new lawn is in your future, begin planning now. August and September are the best months to establish grass, so begin preparing your seedbed now. For more information, see UMaine Extension's publication #2367, Establishing a Home Lawn or call 1-800-287-1471.
Protect raspberries and blueberries from birds and Japanese beetles by covering them with a fine mesh net. To learn more about Japanese beetles and techniques for control, see the fact sheet on the Japanese Beetle issued by the Extension Pest Management Lab or call 1-800-287-0279 ext 1.
Consider constructing a temporary hoop house over a section of your garden to extend the growing season for warm season crops like cucumbers, tomatoes, and peppers. You can drive 3-foot-long rebar into the ground, 3 to 4 feet apart. Place PVC pipe over the rebar and bend to other side. A PVC pipe 20 feet in length makes a nice arch between rebar spaced at 10 feet. Use wood strapping to connect the pipes. Cover with clear plastic. For more ideas on Garden Season Extension, refer to publication #2752, Extending the Gardening Season.
If you have damaged trees from insects, disease, or storms, you may prune these tree parts at any time.
Plant cover crops in your vegetable garden such as oats to recycle nutrients, hold soil, etc. A good source of oat seed is whole oat horse feed from your local feed store. (See article on cover crops)
If you are planning to preserve fruit and veggies from your garden, harvest early or late in the day to prevent water loss. See the Let's Preserve Series for more on canning and freezing.
Consider donating excess produce from your gardens to your local food pantry or Plant-A-Row for the Hungry. To learn more, visit the Plant A Row for the Hungry Web page.
If you think you will not meet your gardening goals for this year, consider purchasing corn, cucumbers, winter squash, potatoes, rutabagas, etc. from a local farmer. Preserve them by freezing or canning or store fresh under the proper conditions. Find a farmer near you by visiting Get Real Get Maine Web site. You can search by county or product.
Dead-heading your annuals will keep them blooming well into the Fall.
Send your diseased tomatoes and potatoes to the pest management office for diagnosis of late blight, etc. Updates on late blight in Maine are available via our hotline at 888-873-8623.

By Tori Jackson, Extension Educator in Androscoggin and Sagadahoc Counties, tjackson@umext.maine.edu

Fall Cover Crops for Home Gardeners
By Richard Kersbergen, Extension Educator in Waldo County, richardk@umext.maine.edu

As the garden season begins to wind down, cover crops should be filling in all the bare spots in your garden.

What are cover crops and what role do they play?

Cover crops are grown to “cover” the soil after the primary garden crop has been harvested to protect the soil during the fall, winter, and early spring. One of the functions of a cover crop is to prevent erosion from washing away organic matter and soil from your garden. They also function to protect the soil from damaging rain drops that can easily destroy soil structure.

Cover crops also play important roles in catching nutrients and holding them during the winter. Nitrogen is easily lost from garden soils when there are no roots or plants to “hold” it during the winter. Cover crops can hold nutrients, improving next year's fertility and protecting the environment from nutrient runoff or leaching.

Other important functions of cover crops are that they add organic matter back into the soil when they are tilled in the following season, providing “food” for the microbial community in your soil and adding beneficial biological life to your garden. Cover crops also help with weed control. By seeding a vigorous growing cover crop in bare areas, they “out compete” many weed seedlings and help to reduce the viable weed seeds in your garden. When they are plowed or tilled back into the soil, they also help inhibit the germination of many weeds due to their “allelopathic” effects. Allelopathic means the inhibition of growth in one species of plants by chemicals produced by another species.

Often the terms cover crops and “green manure” crops are used interchangeably. Cover crops are usually referred to as those crops that are primarily planted in the fall to provide cover, while green manure crops are grown specifically to add organic matter to the soil and are sown at various times throughout the growing season.

So how and what should home gardeners use for cover crops?

Fall broccoli surrounded by oat cover crop
Photo used with permission

Fall carrots surrounded by oat cover crop
Photo used with permission

Probably the easiest way to begin cover cropping is to sow oats in your garden whenever a crop is removed. This practice is good, as it gets you in the habit of removing crop debris in a timely manner and begins the “garden sanitation” process. Oat seed is cheap (I buy “whole oats” or “race horse oats” from a feed supplier instead of buying seed oats that are much more expensive) and easy to grow. Most texts will say to seed at 3-4 lbs per 1000 sq feet, but since the seed is cheap, I recommend that gardeners double that rate. Spread the seed and either till it in 1-2 inches or rake it in. It will grow vigorously this fall and then die this winter, leaving a nice protective dead mat of organic matter on your soil surface next spring. Oats can be sown until about October 15^th in most parts of the state. For those of you who use manure in your garden, a fall application of raw manure followed by an oat cover is a good practice.

Another fall cover crop commonly grown in Maine is winter rye. Rye is like oats in that it grows vigorously in the fall, grabbing nutrients and protecting the soil. Unlike oats however, it survives the winter and grows again in the spring. Winter rye does a better job at holding nutrients than oats. The issue that many gardeners have with rye is that they need to “kill” the cover crop in the spring. Since it grows very fast, it can often become quite tall before many gardeners can get into their garden to till it in. Rye should be sown at the 4-6 pounds per 1000 sq feet and tilled or raked into the soil. Again, rye should be seeded before October 15^th.

Many commercial vegetable growers add a legume to fall cover crops to help build nitrogen in the soil. The most common legume is hairy vetch and is usually sown with rye. It, too, grows fast and would need some good tillage equipment to kill it in the spring. The hairy vetch would be added to the rye mixture at about 1 lb per 1000 square feet.

Remember that as you think about sowing a winter cover crop, also add soil testing and lime additions to the list of “good garden practices.”

Herbal Abundance: Harvesting and Drying Herbs
By Amy Witt, Horticulturist, UMaine Cooperative Extension in Cumberland County, awitt@umext.maine.edu

Echinacea ( purple cone flower)
Photo by Amy Witt

Culinary herb garden
Photo by Amy Witt

Herbs are a wonderful addition to any garden. They are beautiful, fragrant, and serve a variety of purposes. Harvesting and drying herbs in the summer and fall is a great way to make sure you have herbs on hand throughout the winter months.

Harvesting:
Most herbs are ready to be harvested when the flower buds first appear, before they are fully open. The leaves contain the maximum amount of volatile oils at this stage of growth, giving the greatest flavor, medicinal properties, and fragrance to the finished product. Harvest disease-free growth in the early morning (when the oils and active principles are more concentrated) just after the dew has evaporated and before the sun is hot.

Annual Herbs:
Annual herbs can be harvested as soon as the plant has enough foliage to maintain growth and can be harvested until the first frost. Keep in mind that you should only harvest what you can immediately use or prepare for storage. When harvesting, cut just above a leaf or pair of leaves, leaving 4 inches of stem.

If an annual herb is grown for its seed (like dill), do not cut back the plant or use the leaves. Allow the plant to mature fully and form seeds then harvest the seed head when it has turned brown. If you are saving seeds for sowing next season, choose disease-free plants with typical growth and appearance.

Perennial Herbs:
The rule of thumb for harvesting perennial herbs is to remove 1/3 of the top growth at a time. In some instances, you will just remove the leafy tip. Perennial herbs are typically harvested twice during the growing season in early July and again before frost. Carefully prune the plant (using a sharp knife or pruning shears) so new growth will be produced and a compact habit of growth will be maintained. If harvesting flowers like lavender, cut stalks before the blooms open since they will continue to open as they dry. Stop harvesting the herb several weeks before the first frost so the plant has plenty of time to harden off before winter.

Roots:
If you are harvesting roots, the plant must be at least 2 years old. Dig roots in fall when the leaves have changed color or dropped. Excavate the plant from one side, cut a few pieces of root (don’t take the entire root unless you no longer want the plant), and rub it free of soil and fibrous lateral roots. Once the root is dug up, scrub it and cut in into 1/2-inch slices or 2-inch-long pieces (this will allow it to dry more thoroughly and quickly).

Drying Herbs:
Air and heat are two common ways to dry herbs.

Air:
Air drying is the easiest and good for drying all plant parts. For leaves and stems, gather 5-8 stems together and tie them in a bundle (LABEL the bundle), hang bundle in a dark, warm (70-80 degrees F) place for 2-4 weeks. Dry the herb at room temperature; you will know it is dry when it is light and brittle. If the herb bends or is flexible, it needs more time to dry.

When drying roots, spread them out on a tray or screen to dry. Because of their moisture, roots take longer dry.

If you are drying an herb for its seeds, cut the brown seed heads from plant and place them (seed head in the bottom of the bag) in a paper bag (make sure to LABEL the bag). Hang the open bag in an airy place. After the seeds drop off into bag, spread them on a screen tray or in the paper bag until thoroughly dry (2-3 weeks).

Place flower heads (like calendula), short stemmed plants or leaves, on a screened tray rack. Stack them with spacers for air circulation, and place in a warm, dark place until the herbs are dry.

Heat:
Drying in the oven or microwave is the fastest method for drying herbs. However, if herbs are desiccated too quickly at too high a temperature they will lose their flavor, color, and oils. For oven drying, place clean herbs on a cookie sheet, bake at 180 degrees F for 3-4 hours with the oven door open (bake roots at 120 degrees F until light and brittle). If using a microwave, place clean herbs on paper plate or paper towel, set microwave to high for 1-3 minutes, turn stems over or mix leaves every 30 seconds. You can also use a dehydrator following the instructions that come with it.

Freezing Herbs:
Because they lose their color and flavor when they are dried, some herbs (basil, chives, chervil, fennel, cilantro, lovage, and parsley) are better frozen than dried. To prepare, wash herbs, pat dry, take leaves off stems, leave them whole or chop them, put them in a self-sealing freezer bag (larger quantities should be placed on baking sheet in a single layer, frozen, and then placed in a bag), press out any air, label, and freeze. Pureed and herbs mixed with oil can be packed and frozen in ice-cube trays. Once frozen, the cubes can be put into freezer bags. Frozen herbs will maintain their flavor for 6 months.

Storing Herbs:
Once herbs are dried, they tend to look alike and it is almost impossible to remember what they are. It is important to LABEL and DATE your herbs before they are dried and again when they are in their containers. Before storing herbs, make sure they are completely dry. If they are crispy and break easily, they are dry; if they bend or are flexible they need more time to dry. If the herbs are not completely dry when stored, they will become moldy. Store dried herbs in airtight glass jars in a cool, dry place away from light and heat. Herbs should be used within a year of harvesting and drying.

Published and distributed in furtherance of Acts of Congress of May 8 and June 30, 1914, by the University of Maine Cooperative Extension, the Land Grant University of the state of Maine and the U.S. Department of Agriculture cooperating. Cooperative Extension and other agencies of the U.S.D.A. provide equal opportunities in programs and employment.

Call 800-287-0274 or TDD 800-287-8957 (in Maine), or 207-581-3188, for information on publications and program offerings from University of Maine Cooperative Extension, or visit www.extension.umaine.edu.

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