How to Grow an Herb Garden

Good soil is the key to an easy-to-maintain garden. While most herbs are pretty hardy and require little care, you'll still find that a little preparation goes a long way.

Improving Your Garden Soil

Good soil is 50 percent solids and 50 percent porous space, which provides room for water, air, and plant roots. The solids are inorganic matter (fine rock particles) and organic matter (decaying plant matter). The inorganic portion of the soil can be divided into three categories based on the size of the particles it contains. Clay has the smallest soil particles; silt has medium-size particles; and sand has the coarsest particles. The amount of clay, silt, and sand in a soil determine its texture. Loam, the ideal garden soil, is a mixture of 20 percent clay, 40 percent silt, and 40 percent sand.

©2006 Publications International, Ltd. Good soil is key to healthy herbs. See more pictures of culinary herbs.

Some people choose to add vegetables into the herb garden. In the interest of harvesting a bigger and better crop of herbs and vegetables, you'll want to improve the texture and structure of your soil. This improvement, whether to make the soil drain better or hold more water, can be accomplished quite easily by the addition of organic matter.

Organic matter is material that was once living but is now dead and decaying. You can use such materials as ground corncobs, sawdust, bark chips, straw, hay, grass clippings, and cover crops to serve as organic matter. Your own compost pile can supply you with excellent organic matter to enrich the soil.

Each spring, as you prepare the garden for planting, incorporate organic matter into the soil by tilling or turning it under with a spade. If noncomposted materials are used, the microorganisms that break down the materials will use nitrogen from the soil. To compensate for this nitrogen loss, increase the amount of nitrogen fertilizer that you incorporate into the soil.

The next step in your soil-improvement program is to have the soil tested for nutrient levels. The local county Cooperative Extension office can advise you on testing the soil in your area. Your soil sample will be sent to a laboratory to determine any deficiencies of the necessary nutrients needed for successful plant growth. Instructions for taking and preparing soil samples can be found in our article How to Prepare Soil for Planting.

Be sure to tell the laboratory that the samples came from an herb and/or vegetable garden plot. The test report will recommend the amount and kind of fertilizer needed for a home garden. Follow the laboratory's recommendations as closely as possible during the first growing season. We'll talk more about fertilizing below and in the next section, Herb Garden Soil Preparation Techniques.

The necessary nutrient levels are relative to the soil type and the crop being grown. Although different herbs have varying requirements, the soil test institution calculates an optimum average for fertilizer and lime recommendations.

The results of the soil test will indicate the pH (acid-alkaline balance) of the soil as well as the nitrogen content, phosphorus content, and potassium content. The pH is measured on a scale of 1 (most acid or sour) to 14 (most alkaline or sweet), with 7 representing neutral. Most vegetable plants produce best in a soil that has a pH between 5.5 and 7.5.

©2006 Publications International, Ltd. To check your soil texture quickly, squeeze lightly moist soil in your hand.

The pH number is important because it affects the availability of most of the essential nutrients in the soil. The soil lab will consider the type of soil you have, the pH level, and the crops you intend to produce and make a recommendation for pH adjustment.

Phosphorus (P) and potassium (K) levels will be indicated by a "Low," "Medium," or "High" level. High is the desired level for herb and vegetable gardens for both nutrients. If your test results show other than High, a recommendation of type and amount of fertilizer will be made.

Although nitrogen (N) is also needed in large amounts by plants, the soil nitrates level is not usually routinely tested because rainfall leaches nitrates from the soil, which easily results in low levels. Additional nitrogen through the use of a complete fertilizer is almost always recommended.

Tests for other elements are available on request but are needed only under special circumstances.

Adjusting Soil pH

The soil test results may advise you to raise the pH by adding a recommended amount of lime to the soil. Ground dolomitic limestone is best and can be applied at any time of the year without harm to the plants. You may be advised to lower the pH by adding a recommended amount of a sulfur product. Ammonium sulfate is the sulfur product most commonly used. Spread the lime or sulfur evenly through your garden and incorporate it into the soil by turning or tilling.

Fertilizing: How & Why To Do It

Many inexperienced gardeners think that since their herbs have done fine so far without fertilizer, they'll continue to do fine without fertilizer next year. But it's not quite that simple. Although your plants will probably provide you with herbs without using fertilizer, you won't be getting their best effort. Properly fertilized plants will be healthier and better able to resist disease and attacks from pests, providing more and higher-quality herbs.

There are two types of fertilizers: organic and inorganic. Both contain the same nutrients, but their composition and action differ in several ways. It makes no difference to the plant whether nutrients come from an organic or an inorganic source as long as the nutrients are available. However, the differences between the two types are worth your consideration.

Organic fertilizers come from plants and animals. The nutrients in organic fertilizers must be broken down over a period of time by microorganisms in the soil before they become available to the plants. Therefore, organic fertilizers don't offer instant solutions to nutrient deficiencies in the soil. Dried blood, kelp, and bone meal are types of organic fertilizers.

Manures are also organic. They are bulkier and contain lower percentages of nutrients than other natural fertilizers. However, they offer the advantage of immediately improving the texture of the soil by raising the level of organic matter.

Because organic fertilizers are generally not well-balanced in nutrient content, you'll probably need to use a mixture of them to ensure a balanced nutrient content. The table below, as well as the directions on the package, may be used as a guide to making your own mixture. Incorporate the mixture into the soil while preparing your spring garden. Apply it again as a side-dressing midway through the growing season.

When you fertilize with an inorganic fertilizer, nutrients are immediately available for the plant's use. Any container of fertilizer has three numbers printed on it, such as 5-10-20, to indicate the percentage of major nutrients it contains. Nitrogen is represented by the first number (5 percent in this example); phosphorus is represented by the second number (10 percent); and potassium by the third (20 percent). The remaining 65 percent is a mixture of other nutrients and inert filler. A well-balanced complete fertilizer consists of all three major nutrients in somewhat even proportions. A complete fertilizer is recommended for herb and vegetable garden use as long as the nitrogen content isn't more than 20 percent. A typical complete fertilizer used in edible gardens is 10-10-10.

Analysis of Organic Fertilizers

Fertilizer	Nitrogen - Phosphorus - Potassium (N-P-K)
Dried Blood	13 - 1.5 - 0
Kelp	3 - 22 - 0
Cottonseed Meal	6 - 2.6 - 2
Cattle Manure	0.5 - 0.3 - 0.5
Horse Manure	0.6 - 0.3 - 0.5
Chicken Manure	0.9 - 0.5 - 0.8

This is only the beginning in our discussion on fertilization. Keep reading to learn the two-stage program for fertilizing your garden, as well as composting and soil recycling.

Beyond the chemical requirements for fertilization, you also want to make sure that you are supplying the right nutrients for your herb garden.

Fertilizing Your Garden: A Two-Stage Program

1. Broadcast Fertilizing.
   
   When you're preparing the bed for spring planting, apply a complete fertilizer -- such as 10-10-10 -- evenly to the entire garden according to the soil test recommendations. Do not overfertilize. A hand spreader helps keep the job neat as it distributes the granules. Turn the fertilizer into the soil with a hand spade or tiller and smooth out the surface to prepare for planting. This first fertilizing step will see most of your herbs and vegetables through their initial period of growth. Halfway through the growing season, the plants will have used up a lot of the nutrients in the soil, and you'll have to replace these nutrients.
   
   
2. Sidedressing.
   
   As the nutrients are used up by the plants, a second boost of fertilizer will be needed to supply the plants with essential elements through the remainder of the growing season. Use the same complete fertilizer at the same rate as used in the spring, but this time apply it as a sidedressing to the plants. With a hoe, make a four-inch deep trench along one side of the row, taking care not to disturb the plant's roots. Apply the fertilizer in the trench and then cover the trench with the soil you removed. Rain and irrigation will work the fertilizer into the soil, becoming available to the plants.
   

The Gardener's Recycling Plan

The backyard compost pile is the ideal way to reuse most of your garden and kitchen waste and get benefits galore. Composting is essentially a way of speeding up the natural process of decomposition by which organic materials are broken down and their components returned to the soil. The decaying process happens naturally but slowly. The proximity, moisture, and air circulation of a compost pile encourages this process. Composting converts plant and other organic wastes into a loose, peatlike humus that provides nutrients to growing plants and increases the soil's ability to control water.

Composting can save money you would otherwise spend on soil conditioners and fertilizer. It can save time, too, since it gives you a place to dispose of grass clippings, weeds, and other garden debris.

©2006 Publications International, Ltd. This compost pile serves many uses in the vegetable garden.

Garden waste can be turned into good compost in less than a year if the pile is properly managed. When the compost is ready -- coarse, dark brown, peatlike material -- it can be used for many purposes. Compost can be added to potting soil for starting garden seeds indoors. It can also be used as a mulch to protect a plant's roots from the hot, dry summer sun. Compost is also an excellent material to incorporate into garden soil to help control moisture: either increasing the water-holding capacity in sandy soils or improving drainage in heavy clay soils. The more organic matter you add, the more you improve the texture of the soil. Blend the compost into the soil to a depth of 12 inches, making sure it is evenly dispersed through the entire planting area. When compost is added to the soil, it will absorb some of the soil's nitrogen. To compensate for this, organic or inorganic fertilizer and work it into the soil with the compost.

Except for diseased and pest-laden materials or materials that have been treated with herbicides, almost any type of garden waste can be composted. You can also use such kitchen leftovers as vegetable and fruit peels, vegetable tops, coffee grounds, tea leaves, and eggshells. Don't use meat products or greasy foods, which tend to smell bad and attract animals. Composting material should be kept moist but not soggy, and it should be supplied with a nitrogen fertilizer (manure, dried blood, bone meal, or commercial fertilizer) to keep the microorganisms active for faster decay.

Compost forms as organic wastes are broken down by microorganisms in the soil. These microorganisms don't create nutrients; they just break down complex materials into simple ones that the plant can use. Soil microorganisms are most active when soil temperatures are above 60 degrees Fahrenheit, and most of them work best in a moist, slightly alkaline environment. Microorganisms work fastest on small pieces of organic material.

There are two basic types of microorganisms: those that need air to work (aerobic) and those that don't need air (anaerobic). It's possible to compost in an airtight container, thanks to the microorganisms that don't need air. A tightly covered plastic trash can will convert an enormous amount of organic kitchen waste into compost in the course of a winter. The classic outdoor compost pile should be turned regularly (about once every two weeks) with a pitchfork to provide air for the microorganisms that need it.

There are several handy composting devices on the market. Each has its own advantages, but a compost pile need not be fancy to work well. A simple bin made with old cinder blocks, lumber, or fencing material can be used. Tucked aside, but not too far from the garden, the bin can be square, rectangular, or round. It should be four to five feet across and about three feet high.

There are almost as many different methods of composting as there are gardeners. Follow these basic steps of composting to be a success.

How to Start a Compost Pile

1. Start with either a one- to two-foot pile of leaves or 6 to 12 inches or more of compact material, such as grass clippings or sawdust. You can compost hay, straw, hulls, nutshells, and tree trimmings (except walnut). However, unless they're shredded, they'll take a long time to decompose. Use any organic garden or kitchen waste (except meat scraps), as long as it contains no pesticides or diseases.
   
   
2. Over this initial pile spread a layer of fertilizer. The nitrogen will help activate the microorganisms, which in turn will speed the decay of the organic materials. Add about 1/2 cup of ground limestone (most microorganisms like their environment sweet). Then add several shovelfuls of garden soil, which will provide a starter colony of microorganisms. It's handy to have a small pile of soil nearby when you start the compost pile.
   
   
3. Water the pile well. The pile should be kept moist, like a squeezed sponge. Keep adding garden waste to the top of the pile as it becomes available. As the layers become thickened and compacted, repeat the layers of fertilizer, lime, and soil.
   
   
4. About once every two weeks, turn and mix the pile with a pitch fork or digging fork. This will ensure that all the components of the pile, not just the center, will heat up. As the temperature in the compost pile increases, weed seeds and harmful disease organisms are killed, and the decay process will not be delayed.

Now that your soil is ready for your herbs, let's talk about how to plant and grow herbs.

Herbs are useful for cooking, crafting, and decorating -- boldly coming out of the garden and into your home. A separate herb garden is wonderful, but herbs can also be blended with flowers and vegetables in a kitchen or a cottage garden. You can also slip herbs in flower or shrub beds, or even into the plantings around your foundation.

Culinary herbs are a mainstay of most herb gardens. The garden-fresh flavors of thyme, basil, savory, oregano, and marjoram are incomparable. You can also grow gourmet varieties of these classics -- lemon thyme, cinnamon basil, and Sicilian oregano, for example -- to add to your cooking pleasure.

©2006 Publications International, Ltd. If you don't have the space for a separate herb garden, consider growing a selection of herbs in a container.

Plan an herb garden before you plant. Some of the most charming herb gardens have formal beds or geometric patterns that show off the beauty of herbal foliage. Here are some examples:

• Knot gardens interweave herbs with contrasting leaf color and textures into simple or intricate patterns, many of which are taken from embroidery schemes. Simple knot gardens can be made with two overlapping circles or squares set on a background of mulch or gravel. An easy way to make a knot is with annual herbs such as bush basil, summer savory, or sweet marjoram, or even annual flowers such as French marigolds or ageratum.
  
  
• Formal herb gardens generally have symmetrical planting plans, with matched herbs on either side of the garden like reflections in a mirror.
  
  
• Formal and patterned herb gardens often include neat, clipped edgings of boxwood, teucrium, santolina, thyme, winter savory, or other neat herbs suitable for shearing. We'll talk more about planting plans in the next section, Herb Growing Tips.

Provide sandy soil for herbs that need well-drained soil of moderate fertility. If kept in soil that's lean and light and drenched in hot sun, these herbs develop excellent flavor.

©2006 Publications International, Ltd. Grow herbs that need light soil in pots.

• If your soil is naturally sandy and well drained, you're in luck. If, instead, it's damp clay, raise the herb garden and add a 3-inch layer of coarse sand and 2 inches of compost to improve drainage. Avoid excessive use of fertilizers, especially those high in nitrogen.
  
  
• Grow herbs that need light soil in pots. When planted in well-drained, peat-based potting mix, herbs such as thyme, lavender, and rosemary thrive -- and they look great.

Plant perennials that double as herbs in flower beds and borders. Some herbs masquerade as perennials (and vice versa) because they can be used for decorating, fragrance, or cuisine. Some examples include the following:

• Sweetly fragrant bee balm has flowers and foliage wonderful for tea or drying for potpourri.
  
  
• Yarrow bears everlasting flowers for dried floral arrangements. Air drying is fine for golden-flowered forms. To preserve the color of pink, red, and white-flowered yarrows, dry them in silica gel.
  
  
• Lady's mantle is a historical herb with lovely scalloped leaves and small sprays of yellow-green flowers for cutting.
  
  
• Pinks have fragrant flowers that can be used fresh for cut-flower arrangements or dried for potpourri.
  
  
• Use herbs with attractive foliage for season-long color in perennial gardens. Amid the comings and goings of perennial flowers, neatly or colorfully clad herbs maintain enduring style and beauty.
  
  
• Some of the best herbs to grow for decorative foliage include globe basil (small mounds of emerald green), bronze leaf basil or perilla, ornamental sages (with purple leaves, variegated gold leaves, or tricolor green, white, and pink leaves), and silver-leaved herbs such as gray santolina and lavender.
  

  ©2006 Publications International, Ltd. Plant commonly used culinary herbs in a clay planter near a sunny kitchen window for convenience.

• For a great overall color scheme, complement the color of the foliage with nearby flowers.
  
  
• Plant a collection of commonly used culinary herbs in a clay planter by a sunny kitchen window. They will be right at hand when you need them.
  
  
• Restrain rampant herbs like mint and bee balm so they can't take over the garden. These plants need firm limits to keep them in their proper place.
  
  
• Plant rampant herbs in large plastic pots with the bottom removed and the top rim emerging an inch or two above the soil surface. The container will slow down spreading growth enough so you can see trouble before it spills over the edge. Cut back any errant sprouts and use them for tea or to garnish a fruit salad. Divide to renew the chastised plant every year or two.
  
  
• Pinch back annual herbs, such as basil, to keep them from blooming. If allowed to channel energy into seed production, the foliage will grow skimpy and so will your harvest. Pinching off the shoot tips from time to time provides sprigs for herbal vinegars and pestos and inspires the plant to grow back bushier than ever.
  
  
• Remove a few bricks in a garden path to make places for low-growing thyme or oregano. Either herb will thrive in this warm, well-drained location and will give a charming natural look and wonderful fragrance to the walkway.
  
  
• Plant more parsley, dill, and fennel than you think you will use to attract swallowtail butterflies. The beauty of the butterflies and fun of watching the caterpillars develop can be worth the foliage they eat.
  
  
• Harvest perennial herbs as they develop flower buds. This is the time when the fragrant and flavorful oils in the plants are at their peak of intensity, providing a gourmet experience. Because fresh herbs taste so good, even at other times of the growing season, it's perfectly acceptable to continue harvesting whenever you feel the urge. In cold climates, however, hardy perennial herbs need a break from heavy harvesting beginning 45 days before the first frost in order to prepare for winter.

Herbs fit beautifully into any landscape. In the next section, we'll discuss how to plan formal and informal herb garden designs, as well as look at what how to harvest your herbs.

Ground-hugging thyme is a perfect choice for planting between the rocks in a flagstone walk. Tall clumps of angelica or rue provide attractive and dramatic accents in flower borders. Nasturtiums and chives add outstanding floral color to a garden, as well as making attractive cut flowers. The purple-leaf variety of basil is an eye-catching accent in any location. No matter which type of herb you prefer, we can help you design the right plan for your herb garden.

©2006 Publications International, Ltd. This intricate knot garden combines fragrant herbs and shrubs.

Although herbs are often planted in a formal layout separate from the rest of the garden, this is by no means a requirement for success in growing them. Herbs can be mixed into other plantings. The exceptions are those few herbs, such as mint, that will aggressively take over if not curbed. These are best planted in containers or separate beds, where strict control of their spread can be maintained. Most other herbs can be planted along with other row crops in your vegetable garden.

Herbs can be laid out in a very formal or an extremely informal design or anywhere in between. The choice is entirely up to your personal view regarding what will fit best with adjacent garden spaces.

When planning a vegetable garden that includes herbs, the same basic rules of good design apply as when designing any other garden. Tall plants should be located at the rear of side beds, plants of intermediate height in the middle of the bed, and low-growing plants at the front. This way they'll all obtain a maximum share of the available light. In central beds, the tallest plants can be located in the center of the bed, the shortest plants around the outer edge, and the intermediate heights between the two.

The best approach to deciding which herbs to grow is to make a list of herbs you're most likely to use. Write down their soil, light, and water needs; their height and spread; and any special notes such as unusual growth habit. Make a secondary list of plants you might enjoy having if there's any room left.

Sketch the herb garden area to scale (for example, 1 inch on the sketch equals 1 foot on the ground), decide on the size and shape of the planting beds, and determine which of the herbs on your list will be located where. Fill in any empty spots with appropriate species from your secondary list.

Formal Herb Garden Designs

Format balanced geometric layouts usually revolve around some sort of special garden feature, such as a fountain, sundial, garden seat, statue, an unusual feature plant, or birdbath.

©2006 Publications International, Ltd. This formal herb garden layout centers around a monument.

All paths and attention lead to this feature, whether it's in the center of the garden or along one edge.

Informal Herb Garden Layouts

Here are two informal layouts. One backs a wall or fence and the other stands as an island in the middle of a lawn area.

Key The colors in the photos to the left represent the following items: Blue = Monument Grey = Wall / Fence Beige = Low-growing herbs Green = Medium-growing herbs Brown = Tall-growing herbs

©2006 Publications International, Ltd. This informal layout stands as an island.

©2006 Publications International, Ltd. This informal layout backs against a fence.

Harvesting

As a general rule of thumb, herbs have the highest level of flavor in their leaves just before they bloom. Harvesting is best done at this time. In the directory of vegetable and herb plants, you'll find notes regarding the best time to harvest each herb as well as the best methods of preservation.
Harvesting of herbs for fresh use can be done throughout the growing season. Thyme, sage, rosemary, and many other perennials need their active growing shoots snipped in 4- to 6-inch lengths. For annuals collect a few leaves as needed.

When harvesting herbs to preserve for future use, wait until the plant is at its aromatic peak as noted in the directory. Pick it early in the morning when aromatics are at their highest level of the day. Discard any diseased or insect-infested portions. If there is dust present, wash the plant thoroughly and shake off as much of the excess water as possible before processing. If possible, wash the plant a day before harvesting.

Be especially careful when harvesting seeds. The timing must be precise enough to allow the seeds to ripen completely, but they must be caught before they disperse. One way to solve this problem is to keep watch on a daily basis and harvest as soon as the seeds begin to dry. Carefully snip off the heads over a large paper bag, allowing the seeds to fall directly into the bag. Keep them in the bag to complete the drying process. Be careful not to compact the seed heads; air circulation in and around the seed heads is needed to cut down on the possibility of the growth of undesirable molds.

If you cannot keep such close track of the maturation process, another alternative is to enclose each seed head while still on the plant in a small paper or mesh bag once all flowering has ended and the green seeds become obvious. Then, when the heads dry, any seeds that fall out will be captured in the bag. Once you notice that seeds are being released, snip off the heads, bag and all, and dry them indoors.

The most common method of herb preservation is by hang drying. Another good way to preserve many herbs is by freezing them. This method is quick and easy, and the flavor is usually closer to fresh than dried. If you have the freezer space available, freezing is probably the most desirable choice for cooking herbs. Some herbs lose flavor when exposed to air, but they will retain it if stored in oil or liquor. Some herbs don't retain as much flavor when preserved by any means -- they can only be used fresh. You can, however, extend their season by growing them indoors as pot plants during the winter months.

The herb chart below will help you quickly identify those plants best suited to your site. It also notes whether plants are annuals, biennials, or perennials, and how large you can expect each herb to be at maturity. Especially attractive landscape varieties are also identified.

Herb Chart
Key:
Plant: A= Annual, B= Biennial, P= Perennial
Light: FS= Full Sun, PS= Partial Shade, S= Shade
Soil: P= Poor, A= Average, R= Rich, S= Sandy, M= Moist, D= Dry
Culture: E= Easy to Grow, A= Average, D= Difficult, R= Rampant Grower/ Keep Restricted
Height and Spread is in inches.

Name	Plant	Landscape	Light	Soil	Height	Spread	Culture
Angelica	B		FS, PS	A, M	60-72	36	E
Anise	A		FS	A, D	18-24	4-8	E
Basil	A		FS	R, M	18	10	E
Chervil	A		PS	A, M	18	4-8	A-D
Chives	P		FS, PS	A-R, M	8-12	8	E
Coriander	A		FS	R	24-36	6	E
Costmary	P		FS, PS	R	30-36	24	E
Dill	A		FS	A-S, M	24-36	6	E
Fennel	P		FS	R	50-72	18-36	E
Garlic	P		FS	A-P	18	8	E
Geraniums, scented	P		FS	A-R	Varies	Varies	A
Horehound	P		FS	A-P	30	12	E
Marjoram	P, A		FS	R	8-12	12-18	E
Nasturtium	A		FS, PS	A-P, M	12-72	18	E
Oregano	P		FS	A-S	18	12	E
Parsley	B		FS, PS	R, M	12	8	E
Peppermint	P		FS, PS	R, M	24-30	12	E, R
Rosemary	P		FS	S	48-72	18-24	A
Rue	P		FS	P, S	24	18	A
Sage	P		FS	S	20	24	E
Savory, Summer	A		FS	R-A	18	8	E
Sorrel, French	P		FS, PS	R, M	18	10	E
Southernwood	P		FS	Any	30	24	E
Spearmint	P		FS, PS	R, M	20	12	E, R
Sweet, Woodruff	P		S	R, M	6-8	6-8	D
Tansy	P		FS, PS	A-P	40	12-18	E, R
Tarragon, French	P		FS, PS	S-R	24	24	A
Thyme	P		FS, PS	P-A	1-10	12-18	E, R
Wormwood	P		FS	Any	30-48	15-20	A

There are so many different varieties of herbs that we can't begin to describe them all. Instead we've chosen a few of the tried and true varieties to help you as start to grow your herb garden.

^©Publications International, Ltd.