Imagine pinching off your favorite herbs from a vertical herb garden outdoors just steps from your kitchen or patio table. With its spectrum of colors and textures, a productive and aromatic herb wall will provide months of fresh culinary herbs and also double as ornamentals.
Benefits of Herb Walls
Growing vertically uses otherwise empty wall space to free up valuable garden and patio real estate. Not only are herbs easy to grow, but most are low maintenance and have a natural resistance to pests. Also, in their individual containers, plants on an herb wall don't compete against each other or inhibit another plant's growth.
You can grow herbs near the kitchen where you'll be cooking with them — and where you can enjoy them visually. You can also overwinter many herbs indoors to provide fresh herbs after the outdoor growing season ends.
How to Get Your Herb Garden Off the Ground
Select a design with containers that accommodate the plants' root depth. Hardy perennials tend to have deeper roots than tender annuals so they'll require larger containers, generally a minimum of about 8 to 12 inches deep. If planting in the same pot, choose herbs of similar sizes so a large plant won't smother a smaller one.
Because shallow-rooted annuals can thrive in containers 6 to 8 inches deep, they're well-suited for pocket planters. These flexible felt textile or rigid recycled plastic planters are available in various widths and lengths, with depths from 6 to 15 inches or more. Chives are good choices for these planters, as their roots are just 3 inches long. Oregano, tarragon, thyme and basil grow well with just 6 inches of soil. Cilantro and parsley also work well in pocket planters as they're happy with 8 inches of root space.
Lined with landscaping fabric, a pallet easily becomes a vertical herb wall. Even easier, hang various sized individual pots from the slats.
Vertical Wall Planter Rack
Attach a ready-made planter rack to a wall using smooth-coated deck screws, then hang separate containers.
Rectangular Window Box Planters
For planting mint or other invasive herbs, use pot clips or other suitable hardware to hang long rectangular window boxes that will enable the plant to spread out to the sides.
Herbs That Grow Well Together
Pair plants with similar sunlight, soil and moisture needs. Dry climate hardy Mediterranean perennial herbs like rosemary, oregano, sage, lavender, marjoram and thyme need at least six hours of full sun and prefer a dry, sandy, well-drained soil. Moisture and humidity-loving herbs like basil, chives and parsley enjoy a good amount of sunlight and thrive in rich, moist potting mix.
Depending on their growing cycles, herbs can either be perennials that come back every year or annuals that need replacing each year. Feel free to combine perennials and annuals with the same growing requirements, then replace the annuals the following year with a new plant.
Since mint is an invasive plant that will rapidly take over and smother other herbs, it's best to plant it in its own horizontal rectangular planter to enable the roots to spread out. Strong aromatic lemon-scented herbs, such as lemon balm, can alter the taste of milder herbs like parsley, so they too benefit from their own separate containers.
How to Maintain a Flourishing Herb Wall
Locate your vertical herb garden on a surface that offers the particular plants the sunlight they need to thrive. Plant herbs that need a lot of sun, including chives, sage, thyme, rosemary, basil and parsley, on the top tier of your herb wall where they can happily sunbathe and provide shade for plants beneath them that require less sun exposure.
Use a high-quality organic potting mixture, not regular garden soil. Don't overfertilize herbs: Feed them lightly during the growing season every three to four weeks with a half-strength diluted liquid fertilizer and one to three times a year with a slow-release organic fertilizer.
Harvest herbs regularly throughout the growing season when oils are at their peak before they start to flower and while the plant has adequate foliage to sustain growth. Harvest from the top inch or two of the plant, pinching off the tips of each stem just above a pair of leaves. This will encourage the growth of new shoots and create a fuller plant. Annual herbs can be cut back 50% to 75%, but remove only about one-third of the growth at any one time for perennial herbs. Water the roots in the morning and harvest early in the day, before it gets hot and after plants dry off.
Starting Herb Seeds Indoors
If you're looking to save time, you can begin your wall with ready-to-grow herb plants or combine them with others you start from seed. Thyme, rosemary, basil, sage, chervil, chives and tarragon are good candidates for starting indoors. Since many of these have fine seeds that require a long germination period, start seeds in early March so they'll be ready to transplant in mid- to late May, depending on the region.
Bringing herbs indoors before the first frost will keep perennials alive and may extend the growing season for annual herbs. Start by removing any diseased or dead leaves, and be sure your plants are pest-free before moving them indoors. Transition plants indoors gradually so they can adjust to the inside temperature and light, then place them in a sunny location.
Once indoors, rosemary prefers a cool (even cold) sunny location with high humidity as it can dry out quickly. Frequent misting helps, but keep the soil on the dry side, making sure not to water the plant too often as that can lead to root rot. For all plants, be sure to follow the directions on the seed packet.
Herbs are plants that keep on giving as you can dry or freeze them, making them available all year-round.
To start your own herb garden, check out Burpee's wide variety of herb plants and seeds.