Welcome these gray and green herbs to your garden, and flavor is sure to follow.
The subtle-hued, many-textured gray and green herbs native to the Mediterranean are favorites in the herb garden. In their homeland, lavender, marjoram, oregano, rosemary, sage, santolina, savory and thyme cling to chalky cliffs and hillsides and stubbornly exist in barren, dry, sandy, rocky soils. But in our gardens in Maryland (Susan) and Arkansas (Tina Marie), we’ve proved that these Mediterranean immigrants do just fine on American soil with a few amendments. We re-created a Mediterranean region for these plants in our gardens.
The Mediterranean-style garden is a contrast to the look of lush cottage gardens. Picture an arid chaparral in California, or what commonly is known throughout the Mediterranean region by the French term maquis, and as macchia in Italy and matorral in Spain. Imagine creating an alluvial fan with a combination of grit and stone, which in the Mediterranean forms the base around mountains and the raised areas around streams. The canvas is primed with a layer of fine grit mixed with coarse chunks of minerals of gray and green, rust, carbon black and stark white.
Mediterranean herbs like their personal space. We can see much of the mulch, so we know each plant has good air circulation and plenty of interior light. Velvety down on sage leaves and lavender spikes, thick bright green needles of rosemary and the feathery mounds of santolina impart visual and tactile appeal. The colors are a muted palette, ranging from soft silvers and gray greens to blue grays and dark greens, over the canvas of mulch.
Fortunately for us, these gray and green herbs can be cultivated in many climates and soil conditions, do well in containers and can flourish if certain requirements are met. Wanting to make these Mediterranean herbs at home in our gardens or containers and give them the very best conditions for growing, we have created a planting mix to be worked into the soil, a meal mix for nourishment and a mulch to top the soil. Click here for instructions.
You can work our mixes into established beds, or if you want to break ground for a new garden, find a location that has full sun for at least six hours. These herbs need adequate drainage, which means the Mediterranean garden is a natural for inclines or sloped sites. Mark off the garden space and remove all existing plants, destroying any grubs or cutworms as you work. Get a soil test and determine what amendments are needed to improve drainage and nutrient quality, keeping in mind the nature of barren, slightly alkaline Mediterranean soil.
Lay out the placement of the beds and paths with string. Remove the top 6 inches of earth from the pathways and shovel it into the growing areas to make raised beds. The advantage of making new raised beds is better drainage — which should help lessen disease — as well as freshly amended soil and a fairly weed-free garden space to start. Once the raised beds are prepared, fill in the paths with whatever medium you like, such as stone, shells, bark or brick.
Climates and soils vary enormously from garden to garden and from one region to the next. We cannot control the climate, but we can improve the soil to provide a healthy root foundation. We use ground rocks, shells, green sand and — the two most important amendments — builder’s sand and compost. The sand can be purchased from building suppliers and garden centers. Make compost at home or buy composted cow manure at your local garden center. You often can buy worm castings, another valuable soil addition, from a local producer.
Gardens with sharp drainage, good mineral content and alkaline soils are ideal for growing Mediterranean herbs without many amendments. If you have a lot of clay soil, it will drain better with the addition of quite a lot of sand (3 to 5 tons of sand worked into the top 6 inches of soil per 1,000 square feet of garden space). Contrary to popular belief, sand and clay mixtures do not create cement. However, the addition of small amounts of sand may cause clay soil to harden. The solution is to add much more organic matter and sand together, along with the other minerals and charcoal in the recipe. The idea is to use this mixture as a flocculant — the tiny particles that make clay stick together. Adding the Mediterranean aggregate mix and using the Mediterranean mulch introduces particles of differing and larger sizes than those that make up clay. The organic matter, in the form of compost or worm castings, make friendly pockets of bacteria and water/nutrient sponges where plant roots can feed. In this way, water, oxygen and plant roots can penetrate the soil structure.
Excellent drainage is key to helping Mediterranean herbs feel at home in our American gardens. Adding the Mediterranean aggregate and meal mixes, as well as using the Mediterranean mulch in containers is an excellent way to grow healthy herbs when soil conditions are too difficult to alter. Crushed oyster shells are available at farm supply stores. People feed the shells to chickens to produce hard-shelled eggs. Lava rocks come in bags and are available at garden centers. Other ingredients in our mixes, including green sand, granite meal, fish meal, kelp meal and blood meal, may be a bit more difficult to come by (see source list). The goal is to provide a balanced NPK (Nitrogen, Phosphorus and Potassium) ratio, with trace elements and compost to the new garden. Organic plant-food suppliers are listed at the end of the article. The following amendments have been helpful to us as we strive to make Mediterranean plants feel at home in our gardens.
Here are some suggestions for mixes supporting your garden soil’s support of our favorite Mediterranean herbs. The aggregate mix contains minerals that are slowly released into the soil. They enhance drainage until soil acids and bacteria break them down (this takes many years). The Mediterranean meal mix is ‘fast food’ for plants and becomes available very quickly. Feed plants with liquid fish emulsion and kelp or some form of chemical fertilizer to jumpstart and sustain growth. The aggregate mix is the real secret to helping the plants feel at home in American gardens because the minerals in it are similar to the minerals found in the Mediterranean area. They provide immediate soil porosity and long term mineral feeding.
The textured Mediterranean mulch is more of the same idea. In this case, the minerals block fungal spores from splashing onto the bottom of plant leaves, keep the soil cool and moist, discourage weed seed germination and, if oyster shell is added, reflect light onto the underside of leaves, promoting growth. As rain, drought, alternate freezing and thawing, and weeding activities work the mulch into the soil, the mulch becomes a part of the soil structure. Soil drainage, mineral content and pH are slowly altered to nurture the Mediterranean natives. Meanwhile, the mulch provides an interesting texture to the garden.
Aggregate mix is rich in chalk (lime/calcium) and beneficial minerals that are released slowly into the soil, where these particles help the soil drain well. Combine 1 gallon of each of the following four ingredients in a 5-gallon bucket. Mix the ingredients together well. Use 10 to 40 pounds (depending on your soil’s porosity) per 100 square feet of garden space.
When planting Mediterranean herbs, we use this mix in preparing new beds or planting new herbs into established beds or containers. Dig this in about a shovel’s depth so the roots of the plants experience better drainage and have access to the minerals in the mix.
• Activated charcoal (enhances drainage, contains porous carbon, potassium and other minerals)
• Granite meal (1 to 4 percent total potash and grit)
• Greensand , or builder’s sand, is the name commonly given to a sandy rock or sediment containing a high percentage of the mineral called glauconite (contains marine potash, silica, iron oxide, magnesia, lime, phosphoric acid and 30 other trace elements, and also retains water)
• Oyster shell (35 to 55 percent calcium, 40 percent carbon dioxide, trace amounts of aluminum, copper, iron, magnesium, manganese, phosphate, silica, zinc, organic matter, chlorine, fluorine and nitrogen.) Note: Oyster shells should not be used in soils that are already alkaline.
Mediterranean meal mix is added to provide a balanced “fast food” for new plants. It is in powder form that becomes available to the plants quickly. Combine equal parts of the following meals into a 1-gallon container. Mix the ingredients together well. Use 3 to 9 pounds (the lesser amount for fertile soil that just needs a boost and closer to 9 pounds for very poor soil or a new garden) per 100 square feet. When we create new beds, dig holes for new plants in established beds or transplant new plants into containers, we use this meal mix. Mix it into the soil, about a shovel’s depth so that plant roots have access.• Bone meal (5-12-0 plus 15 percent calcium)
Textured Mediterranean mulch acts as a barrier between lower leaf surfaces and soil-dwelling fungal spores. It cools the surface of the soil, conserves moisture, breaks down very slowly and is attractive. In humid climates, a light-colored mulch reflects light toward the plant and discourages fungal diseases.
Combine equal parts of the following ingredients and mix together well. Apply to soil surface, 1/4 to 1/2 inch thick. The ingredients in this mulch vary in size and make an attractive, multi-textured, multi-colored mulch for the gray and green herbs. We use this for herbs in the garden and in containers.• Activated charcoal
Water can be a matter of life or death to plants, and water requirements change during different seasons of the year. Mediterranean herbs need regular watering when they are first planted for the establishment of new roots. During hot, dry summer months, they will need thorough watering about once a week (depending on your climate), preferably in the early morning. Soaker hoses are the healthiest and most efficient way to get water to the garden. Avoid wetting the leaves in the heat of the day and before sundown. Water droplets magnify light rays and cause leaf burn. Water left on foliage after dark spreads fungal disease.
During the winter, the plants use less water for respiration and transpiration. Excessive water stays around the roots and can suffocate a plant. Lack of oxygen and soggy organic matter encourages the growth of fungal diseases. Nonetheless, it is important to keep the soil from drying out completely during the winter.
Organic plant food such as fish emulsion and liquid kelp can be used as needed in the watering solution and as a foliar spray during the growing season. During the spring and summer, plants are growing actively and use nutrients quickly, but you should cut back on feeding during the winter months. Overfeeding nitrogen in winter is not only a waste of resources but also may cause disease symptoms in your plants.
The first line of defense in organic pest control is to grow healthy plants. Enjoy and examine herbs regularly, particularly in the early morning. Insects are still at rest, and the temperature is usually pleasant. When pests move in, the first control is to spray the plants with strong streams of water; some pests can be picked off by hand. Blast away aphids, scale, spider mites and mealybugs. If a pest is feeding, its proboscis most likely will stay in the plant as the rest of its body is swept away. Summer or horticultural oil will smother adult and larvae forms of pests. Soap dissolves the mantle of many adult and larvae pests. Neem repels and disrupts feeding and mating cycles of pests. Repeat controls as needed to interrupt the reproduction cycle of pests.
Discard all pest-ridden or sick plants. Plants chronically infested with pests weaken the entire garden. Sick plants are hosts for fungal diseases that spread on air currents, on moving physical surfaces (like bugs and fingers) and through water on plant surfaces and in the soil. Remove and discard these plants into the trash, not the compost. Mulching with our Mediterranean mulch will help discourage fungal diseases.
Many species of subshrubs are native to the Mediterranean region. They all require a minimum of six hours of sun and good drainage. When planning your garden, remember to visualize each specimen as a fully grown plant, allowing generous space for air circulation. We successfully grow many varieties of common Mediterranean gray and gray/green herbs such as lavender, sweet marjoram, oregano, rosemary, sage, santolina, thyme and winter savory in our gardens and containers. They thrive because we try to give them elements of their native habitat.
(Lavandula angustifolia, L. dentata, L. stoechas, L. xintermedia)
This shrubby perennial with gray-green foliage and lavender spikes is famous for its perfume. Blooms vary from blue-purple to lavender, pink and white. Most lavender species and hybrids grow from 1 to 3 feet tall, although there are some whose flower spikes reach 4 feet. Gardeners living in hot, humid climates must attend to lavender’s need for excellent drainage and air circulation. Prune in spring after new growth begins, removing deadwood, and cut back again after flowering. Note: L. angustifolia and L. intermedia are hardier, while L. dentata and L. stoechas are more tender.
Marjoram (Origanum majorana)
Sweet marjoram grows into a petite bush with wiry stems and small, perfumed, greenish-gray leaves topped with pale purple-violet to white flowers. Sweet marjoram is a perennial only in mild Mediterranean-like climates. For those of us in cooler regions, this savory herb can be grown as an annual or overwintered in the greenhouse or a sunny window in a well-drained container.
Origanum majoricum is sold as Italian oregano, Sicilian oregano or hardy marjoram. It is a hardy perennial, surviving northern winters if it is planted in a well-drained location. It attains 2 feet in height when in flower and will increase in breadth to 4 feet across. Origanum ‘Kalitera’ has small, fragrant gray leaves — it is very similar to O. majoricum — with a smaller, more polite growing habit. The origanums are hugely varied with dark green fuzzy leaves to golden and lime green in color, and a flavor to suit every palate.
Rosemary plants come in two major forms, upright and prostrate. In some mild climates, upright forms grown in the garden may reach 5 feet tall and 5 feet across. Lower limbs will root and increase the diameter of the planting. Prostrate varieties do not grow as tall, and some varieties planted to spill over a wall will hug it flatly all the way down to the path. The needle-like leaves of this tender perennial are green to gray on top and sometimes white on the underside. Rosemary varieties may be selected to bloom blue, pink or white. Hardy varieties include ‘Arp’, ‘Herb Cottage’, ‘Hill Hardy’, ‘Salem’ and ‘Severn Seas’.
Although subtle, the soft hues and textures of sage’s gray-green foliage stand out among the various bright greens of other culinary herbs. In season, garden sage has purplish-blue flowering spikes. It grows to about 2 to 3 feet tall and about 3 feet in diameter, with a pleasant mounded shape. Sage wants full sun, although it will tolerate partial shade if air circulation is good. After sage is established in a well-drained location, it needs little care. Spring pruning, deadheading and occasional watering is sufficient to maintain healthy sage. Many variegated sages add wonderful color as well as pebbly and velvety texture to the garden.
(Santolina chamaecyparissus, S. pinnata, S. virens)
Santolina chamaecyparissus, also known as lavender cotton, is an aromatic evergreen shrub with finely divided, gray-green leaves and wooly white stems. Generally they are slow growers, not much taller than 2 feet in height, and there are a number of dwarf varieties, which stay close to the ground. They grow in soft-mounded shapes and send up stems with little, bright-yellow, button-shaped flowers in summer.
S. virens (also known as S. viridis) is the green-leaved santolina. The green lavender cotton leaves appear to be narrower and not as thick as the wooly gray leaves. The green-leaved plants are said to be hardier. S. pinnata can be found with both green and gray leaves, which are a bit more feathery in texture than those of S. chamaecyparissus, and is one of the taller santolinas.
Santolinas tend to separate in the center of the clump as lavenders do. Be sure to prune them back in the spring to help control this trait. In cold winters, santolina may die back, but be patient and it may send out new growth in the spring.
(Thymus vulgaris, Thymus ‘Argenteus’, T. xcitriodorus)
Thymes grow best in sandy soil. Most of the culinary thymes are hardy evergreens to about Zone 4 or 5. These small woody perennials can range from 6 to 15 inches in height; some hug the ground in a mat, and some grow upright. Flowers vary from pink to purple to white.
It is important to prune thymes several times a year, especially where summers are hot and humid. Prune in early spring, when temperatures begin to warm, then when flowers form and again about mid-summer. The last pruning should take place about 45 to 60 days before the first frost is anticipated in your area. This will help to keep the plants from getting too woody, and will help discourage fungal diseases.
Winter savory (Satureja montana)
Winter savory is a semi-evergreen perennial, which grows to about 18 inches tall and about 2 feet in diameter. It prefers neutral to slightly acid soil. It has a rather stiff appearance with its upright growth habit, woody stems and needle-like pointed foliage.
It is a hardy perennial and can become somewhat shaggy-looking if left to grow on its own, so shape it in the spring and prune again after flowering. The tiny blooms are white to pale lavender.
— Susan Belsinger is a longtime contributor to The Herb Companion. She writes, cooks and gardens from her home in Maryland. Tina Marie Wilcox enjoys gardening in the Heritage Herb Garden at the Ozark Folk Center in Arkansas.
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