Herbs

Herbs in Window Boxes or Pots on Patio or Balcony:

If you don't have room for herbs in your garden, consider planting herbs in other methods. Choose a sunny south window for your herb window box, and fill it with a good potting mix with added perlite and vermiculite. Use four plants in a 2' window box, or six plants in a 3' box.

Pot an herb mixture in halved old wine barrels, large terra cotta pots or urns and place on your patio, porch or balcony. An elevated saucer on wheels makes it easy to rotate the pots and keeps algae and mold from growing underneath. Some include a bowl underneath to catch excess water.

Many herbs lose flavor if they are fed too much fertilizer, so use half strength garden fertilizer or a half dose of slow release fertilizer. Keep watered well, especially in the heat of summer. Most herbs will do well with at least 1/2 day of sunlight, but prune them often to maintain bushiness.

Consider: basil, parsley [flat-leafed is best for cooking], tarragon, various thymes, including lemon, various mints, especially spearmint, fennel, marjoram, oregano [Greek is a favorite], basil [including purplish opal], rosemary [which can grow quite tall and round], and sage.

Some herbs will stop growing and/or die back in the heat of summer. This is of no concern...it is their normal reaction to the heat and bright sun. Don't overwater them during this time of temperature stress. If the roots are kept waterlogged, they could rot since the foliage is not needing as high a volume of water to grow. The herbs will recover when the temperature cools.

Here are some suggestions to keep your herbs healthy through the summer heat:

Work a little lime into the soil around many herbs, as lavender, sage, thyme and rosemary to bring the pH up a little [make alkaline]. Pinch back scented geraniums to healthy vegetative buds to make them bushy. Separate plant side shoots, giving them space to grow and produce. To help keep the soil evenly moist, place a mulch around your herbs. Avoid mulches that increase the acidity [lower the pH] of the soil such as peat, pine straw or oak leaves. Mediterranean herbs (marjoram, oregano, rosemary, sage, winter savory and thyme) prefer not to be mulched. They enjoy the heat and dryness more than other herbs.

Belinda writes~ I am growing fresh herbs for the first time outside. They are doing well and I need information about how to preserve them for kitchen use.

Herbs are at their flavor peak when they have just been harvested. Mid-morning [just after the sun has dried the leaves but before it is too hot] is the best time to harvest. Cutting back as much as 3/4 of the plant will not harm it. If the leaves are dirty, rinse in slightly cool water and dry immediately with paper towels.

The best time of year to harvest is before the flowers bloom. You can prolong the optimum harvest time by pruning off all flower buds as they form, but eventually the harvest season will come to an end, and it is time to preserve your crop.

Freezing or preserving in olive oil are the best ways to save herbs, but many gardeners prefer drying because it is easy and does not require special storage. Hang bundled herbs in a cool airy place and cover with a paper bag. Make sure your herbs are tied in bundles small enough that they do not touch the sides of the bag when they are covered, then tie the end of the bag closed. After about three weeks, the herbs will be dry and crumble easily into jars for storage. Use dried herbs within six months of harvest and then discard, as their flavor decreases rapidly.

Assistance from: Garden Guides

Pearlene writes~
In the recent newsletter regarding your suggestions on drying herbs, you say to put small bunches in paper bags, but not to let the herbs touch the bag. I want to know why. I have always dried my oregano in large paper grocery bags. Am I doing something wrong?

A. If your method works, please do not change it. Not having the leaves touch the bag is a warning that the paper can get moist from the leaf evaporation as the herbs dry. If this moisture remains on the bag and touches the leaves, mold, mildew or fungus can result, thus giving your dried leaves a musty smell and therefore an off-taste.

Nancy writes~
I just purchased eight common herbs and planted them in two containers. I do this several times a year and they always die. Please give me some advice on how to keep them alive and "well". I have basil, Italian parsley, regular parsley, dill, rosemary, chives, thyme and a small hot pepper. Should I put fertilizer on them and if so, what kind? I want so much for them to live; love cooking with herbs.

A. Many herbs can be grown successfully in containers on a patio or balcony. Container growing is recommended for herbs that need good drainage and tend to rot in overly wet garden soils. Any container is suitable for growing herbs as long as it has a drainage hole. Clay pots are often preferred because they are more porous than plastic. Soil should be loose and well-drained, made by mixing equal parts of potting soil, peat moss, and perlite (or vermiculite). Window boxes, strawberry jars and large pots can accommodate a combination of several herbs. Watering is the most difficult part. Plants grown in containers dry out faster than in the ground. On a hot, sunny day, a container may require water once daily. Water requirements vary from plant to plant. When the top of the soil feels dry, apply enough water to allow a small amount to come out the drainage holes in the bottom of the container. Since most herbs do not require high fertility, you should not need to fertilize them as much as you would other container-grown plants such as flowers or houseplants. Give them a 20-20-20 once or twice a month. Pinch plants back to keep bushy and compact and remove any dead or diseased leaves. Herbs growing in containers can be easily moved indoors for the winter. Before doing so, the plants should be acclimatized in early fall. Gradually move them indoors a few hours at a time over the period of several days so they get adjusted to the differences in temperature and light. Herbs growing indoors should be treated differently than those out-of-doors. Provide sufficient light to keep the plants from getting spindly. Grow them in the sunniest location you have or under fluorescent lights. Since the plants will not be using as much water as they did outdoors, water only when the soil is dry to avoid root rot. Check frequently for aphids, spider mites, and whiteflies which are common pests on herbs grown indoors.

Assistance from The Illinois Cooperative Extension Service

Sandra writes~
I love the taste of fresh herbs. I have tried in the past to grow them in the house over the winter with no luck. Is there any advice you can give me?

A. Growing herbs inside requires good drainage, sunlight and adequate water. A south or west windowsill provides a good spot for an herb garden. For potting medium, mix two parts sterilized potting soil and one part coarse sand or perlite. There should be 1" gravel in the bottom of each pot for drainage. Bringing your herb garden indoors for the winter is one way to ensure flavor for winter casseroles, soups and stews and to protect your plants from winter weather. Biennial and perennial herbs may be transplanted to indoor containers. New plants also may be started indoors for winter growing. In spite of its problems, many people grow parsley inside. Dill grows to about 3' so that is not a good choice. Basil is good, but it is an annual, so expect to sow some more as the seasons pass. Basil needs high light so tends to get leggy with long spindly growth and few leaves. Rosemary grows inside successfully but keep on the dry side as it is Mediterranean. Peppers can be grown inside, but they like bright light and in order to have fruit the flowers must be hand-pollinated. Grow lemon-scented [or other scents] geranium and ginger inside over the winter, but take them outside during the summer.

Assistance from: http://www.urbanext.uiuc.edu

Sheila writes~
I would like to have herbs in my home. Please tell me how to grow rosemary, thyme and other herbs at home.

A. Freshly harvested herbs have pungent and aromatic qualities that far exceed those of their commercially obtained counterparts, whether fresh or dried. Even after the outdoor growing season is over, you can still enjoy dried herbs in fragrant potpourris and sachets. You can also grow herbs indoors in pots on sunny windowsills, and use them for culinary purposes, either fresh, dried or frozen. Their culture is easy, require little care and space, have very few insect and disease problems and generally require only moderate fertility levels. Herbs flourish under the same conditions provided for a flower or vegetable garden. Although most herbs will grow in partial shade, it is better if the herb garden receives at least 4-6 hours of sunlight a day. A majority of herbs will grow well under a wide range of soil conditions, with the exception of extremely wet, poorly drained soils. If the garden soil is poorly drained, you can improve the situation by modifying or amending it. Even more effective would be the use of raised beds. Herbs do better in soils of low to medium fertility, so additional fertilizer applications are not needed. Soils with high fertility tend to produce lots of foliage that is low in flavor. Prepare garden site in the same manner as a vegetable garden, spading it to a depth of 6-12". Then level and rake the site to remove any large clods and debris. The garden size will depend largely upon the quantity of herbs needed and want to grow. A dozen annuals and/or perennials will provide you with a good variety. Most herbs look great in May and June, then get scraggy and unattractive the rest of the season. For this reason, they are often informally combined with annual and perennial flowers, trees, shrubs, groundcovers, vegetables or other plant material. This allows to take advantage of the various colors, textures, sizes, and shapes that other plants have to offer. Some gardeners prefer to select a specific theme for their herb garden and choose the herbs accordingly. Some examples are a kitchen garden (including thyme, sage, basil, tarragon and dill); a single color garden such as gray-green (as horehound, lavender, artemesia and wormwood); a scented garden (including mint, scented geranium, lemon balm, thyme and rosemary); or a garden with different varieties of a specific herb (many sages or thymes). Colors can also be used in combination; some colors blend together better than others. For example, a silver-foliaged plant such as horehound enhances a red or pastel foliage or flowers. Yellow and blue is always a good combination. Orange and blue, yellow and violet, and red and green are complementary colors and create a strong effect. Contrast is another technique to use to make the garden more interesting. By definition, contrast is using opposing elements close together to produce an intense or intriguing effect. You can contrast textures, darks, lights, colors, shapes, lines, flower form, flower height...any design element. There are many reasons why you may want to grow herbs in containers rather than in the garden. Many are small and tend to get lost in a landscape; growing them in containers brings them closer to the viewer. This is especially true of ornamental herbs that have unique qualities that should be viewed up close. Container growing is especially recommended for herbs that need good drainage and tend to rot in overly wet garden soils, or for tender herbs that need to be overwintered indoors. Containers are easily transported and can be arranged in attractive groupings with containers of flowering plants. Any container is suitable for growing herbs as long as it has a drainage hole. Clay pots are often preferred because they are more porous than plastic. Other containers that work well include window boxes, strawberry jars and hanging baskets. The soil you use should be loose and well-drained. A recommended mix for container grown plants can be made by mixing equal parts of potting soil, peat moss and perlite (or vermiculite). Small and slow-growing herbs look best in containers. Some examples are variegated sage, purple sage, golden sage, parsley, Greek oregano, rosemary, marjoram, bush basil, thyme, chives, and summer savory. Window boxes, strawberry jars, and large pots can accommodate a combination of several herbs and flowers. Watering is the most difficult part of container gardening. Plants growing in containers dry out faster than in the ground. On a hot, sunny day, a container may require water once or twice daily. Of course, the water requirements vary from plant to plant. When the top of the soil feels dry, apply enough water to allow a small amount to come out the drainage holes in the bottom of the container. Since most herbs do not require high fertility, you should not need to fertilize them as much as you would other container-grown plants such as flowers or houseplants. During the growing season, pinch the plants back to keep them bushy and compact and remove any dead or diseased leaves to keep them healthy. Herbs growing in containers can be easily moved indoors for the winter. Before doing so, the plants should be acclimatized in early fall. Gradually move them indoors a few hours at a time over the period of several days so they get adjusted to the differences in temperature and light. Herbs growing indoors should be treated differently than those out-of-doors. One of the biggest problems is providing sufficient light to keep the plants from getting spindly. Grow them in the sunniest location you have or under fluorescent lights. Since the plants will not be using as much water as they did outdoors, water only when the soil is dry; apply enough water so that some drains out the bottom of the pot. Avoid overwatering which will cause the roots to rot. Check the plants frequently for aphids, spider mites and whiteflies which are common pests on herbs grown indoors. Your herb garden will need attention throughout the growing season. Weed control and provision for adequate moisture are two important cultural necessities. When rainfall is less than 1" per week, provide additional moisture. The use of a mulch is an attractive and effective means of controlling weeks and maintaining constant soil moisture and temperature for the root systems of your herbs. Mulches that you might consider include bark chips or shredded bark, compost, ground corncobs, pecan hulls, or dried grass clippings. To be effective, the mulch should be applied at least 3" deep around the plants. Most perennial herbs are hardy plants that are able to survive winter. However, winter weather can be severe. Sometimes herb plants succumb to the extreme temperatures but often they are killed by extreme temperature fluctuations. Here are some suggestions to ensure plant survival. First, start out with healthy plants and maintain vigor throughout the growing season. Though many herbs tolerate poor or wet soils, the majority prefer to grow in well-drained soils. Plants in overly wet soils will grow poorly and are subject to root rots. Soils that are heavy should be amended with organic matter to loosen the clay structure. Another method of improving drainage is to plant the herbs in raised beds. Avoid late fertilizing and pruning. Most herbs are more flavorful when the fertility is not too high. Pruning should be done during spring and summer; avoid excessively cutting the plants back in the fall. The growth serves to catch leaves that help insulate the plants. An additional mulch of evergreen branches or some other material should be placed around the plants. Avoid a mulch that packs down and stays too wet during the winter, which would cause the plants to rot. Plants that are marginally hardy (such as rosemary and Greek oregano) should be dug up, potted, and overwintered indoors. They can be moved back to the garden the following spring. Herbs are at their peak of flavor when they've just been harvested. Midmorning, just after the sun has dried the leaves but before it's too hot, is the best time of day to harvest. You can cut back as much as 3/4 of the plant without harming it. If the leaves are dirty, rinse them quickly in cold water and dry them with paper towels. The best time of year to harvest is before the flowers bloom. You can prolong the optimum harvest time by pruning off the flower buds as they form, but even the most attentive bud-nipper will find that the harvest season will eventually come to an end, and it's time to think about preserving some of your crop.

James C. Schmidt, The Illinois Cooperative Extension Service.