Soil Preparation – Before planting your herbs, we recommend carefully accessing and preparing the soil so that it has proper drainage. In North Texas, our heavy, sticky clay soil needs to be amended before you plant a new bed. Plant roots don’t get enough oxygen in clay soils. Raised beds, compost and other amendments help. Back to Earth composted cotton burrs and expanded shale are two of the best soil amendments to ensure success in your raised beds and mixed borders. Expanded shale, a gravel-size rock that is pumped full of air, aerates clay soil, makes it easy to work and helps it drain better. You only need to add it to the soil once and work it in:
• Till in 3 inches of expanded shale, 6 to 8 inches deep into existing weed free soil
• Till in 2-3 inches of composted cotton burrs
• Mix the expanded shale, compost and soil thoroughly
Top dress the bed with Landscape Mix.
Covington’s Soil Builder is a combination of expanded shale, composted cotton burrs and Texas greensand which can be used as a one-step application to save time and labor.
A raised bed garden is a garden built on top of your native soil, sometimes incorporating native soil, sometimes not. Raised bed gardens can be contained, such as when you build a wood or stone structure to keep the bed intact, or they can be more free form, with soil and amendments merely piled several inches high.
You can plant anything from herbs and vegetables to perennials and shrubs in a raised bed. The soil in a raised bed will warm sooner in the spring and raised beds allow gardening in poor soil areas, production is improved, and you gain accessibility, due to the higher than ground level plants and herbs.
Proper bed preparation allows plant roots to adjust and begin to grow more rapidly and deeply. Mulching will save you time and money because mulch keeps moisture in, but protects plants from heavy rainfall or extreme temperatures. Mulching also keeps weeds away. Good choices are hardwood, cedar or cypress mulch.
Many herbs prefer moderate to dry conditions and require good drainage in both containers and raised beds. It’s easy to correct poor drainage with expanded shale. It is important to always ‘deep water’ your plants rather than a light sprinkling, especially during the hot summer months. Encourage deeper root growth by soaking the soil, and then letting it become dry an inch or two down before you water again. When growing herbs in containers, combine several with the same watering requirements. Basil and cilantro are examples of herbs which prefer moist soil. They are not cold hardy, so plant them in their own container or with other varieties within the same herb family so you can bring these containers indoors in the event of a late freeze.
Most herbs prefer full sun, for those that do, 6 hours per day is ideal. In North Texas you might consider planting those herbs that tolerate part shade, in morning sun and afternoon shade conditions. Mints, chamomile, bee balm, catnip, basil, chives and lavender are examples of some herbs which would benefit from some shade in the afternoon (mints will thrive in a mostly shady condition but are also tolerant of full sun).
Herb Gardening in Containers – Herbs can be grown very successfully in containers and are a practical solution for people who have limited gardening space. You can easily move the containers to a warmer area if needed and back into the shade if the season gets too hot. Group containers together as close to your kitchen door as possible for easy access. Almost any container can be used for planting herbs as long as it has adequate drainage holes. Plant herbs on their own or in combination with other herbs. Leave ample space for all plants to grow. Prune faster growing herbs regularly so they don’t overgrow the slower ones.
Fertilizing Herbs – Fertilize with products such as Bioform, Blood & Bone Meal, Happy Frog Tomato & Vegetable fertilizer, or a balanced timed released fertilizer such as Covington’s Premium Flower & Garden Fertilizer. In general, herbs require only a limited amount of fertilizer. Too much fertilizer encourages leafy growth at the expense of the volatile oil, which gives the herb plant its flavor.
Most herbs are herbaceous (non-woody). Some herbs, such as lavender, rosemary, hyssop, some sages and basils may become semi-shrubs with woody stems, especially in temperate zones. These herbs are better suited for raised beds and large containers.
Annuals, Perennials and Biennials – Herbs classified as annuals have but one season of growth, though some of them reseed. Biennials have two seasons of growth, producing leaves the first year and then flowering and setting seed the second year. Perennials have ongoing growth, some last several seasons; others many years.
Perennials may die back to the ground in winter and re-emerge from the crown (with the exception of those herbs which are evergreen). Don’t be hasty to remove perennials, as some are slow to show new spring growth.
Soil mix for container grown herbs – 2/3 Covington’s Potting Soil & 1/3 Expanded Shale
Themed Container Gardens are fun and make great gifts. Plant the ones you and your family like most:
• Italian Chef – Sweet Basil, Italian Parsley, Oregano, Marjoram, Thyme, and Trailing Rosemary
• French Chef – Tarragon, Chives, Sage, Trailing Rosemary, and Curly Parsley
• Tea Pot – Bee Balm (dwarf), Chamomile, Lemon Balm, Peppermint, and Stevia (medium container)
• Perfume Pot – Lavender, Lemon Scented Geranium (Citronella), Pineapple Sage, and Lemon Balm (large container)
Additional Tips for Success with Herbs:
Harvest herbs regularly to promote stem and leaf growth, to keep flowers from forming, and to keep herbs producing for a longer period of time. Herb plants will look better and be healthier if pruned back regularly.
Do not allow your herbs to flower early in the growing season…this is a signal that its life cycle is about to end. Your herb is making a flower, then a seed, and then it dies back for that season. It is best to keep any flowers from forming in the first place by pinching the flower/bud off.
Do not spray chemicals onto herb plants. There are many ways to keep ahead of the problems that may otherwise need chemical applications. Weed regularly, watch your herbs closely for insect attack, and fertilize properly. Herbs are rinsed and used fresh, so don’t exposed them to treatment that may be dangerous or toxic.
Herbs in the mint family tend to be vigorous and some varieties invasive, so it is better to plant in containers.
If you plan to harvest the leaves of certain varieties of herb plants quite often for cooking, etc., you may want to plant at least 3 of each plant to ensure a steady supply (exception: most mint and well-established chives).
Most herbs require good drainage but success in the cultivation of Lavender, Rosemary, Sage, and Thyme is dependent upon it.
Herbs have many benefits beyond their many obvious uses – Many of the creeping thymes, mint and chamomile are excellent between stepping-stones and in rock gardens; chives are natural pesticides; and some herbs such as dill, fennel and parsley attract beneficial insects to your garden. Their low-lying flowers make good homes for the insects that will help your garden to thrive. Several herbs are attractive to butterflies and bees, and are worth planting to encourage the fertilization that comes along with these helpful insects. Bees and butterflies especially love anise hyssop, thyme and sage.