Welcome to the fourth lesson of Kitchen Garden School at Cornell Farm. This month, we're focusing on all things herbs — from an exploration of their culinary and medicinal value to their role as companion plants in our vegetable gardens and beyond. So, without further ado, let's learn about herbs!

What Makes an Herb?

To riff off of Shakespeare, you might be asking yourself: "What's in an herb? Would rosemary by any other name smell as savory?" While there is no singular definition for an herb, when gardeners use the term, we are generally referring to leafy green plants that are used for flavoring foods and beverages. In other contexts, an herb might be a plant that is used to make a tea, cream, oil, poultice, salve, or tincture used in the treatment of a certain ailment.*

You will often see the two distinguished as culinary and medicinal herbs for this reason. But these aren't necessarily mutually exclusive: Mint, rosemary, lemon balm, basil, catnip, and parsley — just to name a few — are all leafy green plants with both culinary and medicinal properties and uses. In fact, the compounds that make many culinary herbs so delicious and aromatic are the same ones from which natural medicines are derived.

In nature and in the garden, these compounds are an herb's natural defenses — often against insects and disease — which makes them great companion plants for a wide variety of plants that can benefit from being grown in the same vicinity.

Companion Planting with Herbs

Companion planting is a time-honored practice of growing two plants close together for the benefit of one or both plants. These benefits can include:

Pest deterrence: Many herbs, like garlic and rosemary, have unappealing aromas to insects that want to eat other plants in your kitchen garden, encouraging them to search for a meal elsewhere.
Attracting beneficial insects: Some herbs, like dill and yarrow, attract beneficial insects such as ladybugs and lacewings, which prey upon these pest insects.
Pollination for better fruit set: Herbs that flower, like lavender and basil, can attract pollinators like bees and hummingbirds (which have the added benefit of eating aphids and other insect pests), and better pollination means more fruit.

Check out the video below for more tips on companion planting with herbs, including some specific combinations.

For more ideas on herbs that can be companion planted with various other plants in our vegetable gardens, feel free to consult the handy-dandy companion planting chart we put together.

Planting an Herb Pot

When considering companion plants, it benefits you to choose plants that already want similar growing conditions. For example, Mediterranean herbs like rosemary, oregano, and thyme, will appreciate sharp-draining soil. This is an important consideration any time you are growing plants together — for instance, in an herb pot. No matter the size of your kitchen garden, an herb pot is a great way to bring a bit of herbal goodness into your space, as Cynthia explores in the video below. Check out her herb combinations based on common cultural requirements.

A Spotlight on Rosemary

One of our favorite herbs — rosemary — just so happens to do double-duty as both a culinary and medicinal herb. And in the video below, our very own Juan Posadas, a student of herbalism who distills his own essential oils, explores the many uses of this Mediterranean marvel.

As Juan remarks, rosemary is a "one stop shop" for culinary, medicinal, and ornamental purposes. As an evergreen perennial, it looks good and provides structure in the garden year-round. And thanks to the presence of several notable compounds, it not only perfumes the air and flavors our food, but can be used to impart many health benefits. And to top it all off, it's pretty easy to grow!

Traditionally, rosemary has been used as a memory enhancer, as a cleanser, and in hair treatments — uses that have been supported by scientific research. Rosemary contains betulinic acid, which is noted for its antimicrobial qualities; carnosic acid, which has been shown to have neuroprotective qualities; and rosmanol and rosmarinic acid have antioxidative properties, as they scavenge for free radicals in the body.

As a member of the Lamiaceae or mint family, it a cousin to many other culinary herbs, including lavender, thyme, and oregano, and if you're walking through your herb garden, you will likely notice similarities between all of their aromas, which is thanks in part to the common presence of camphor, thymol, and geraniol — among other compounds. The leaves and stems of rosemary, in particular, contain some of the highest essential oil content of any plants in the Lamiaceae family, and to maximize their potency, they should be harvested under cool, dark conditions when the plants naturally produce the most oil. Rosemary essential oil is soluble in water, vinegar, oil, and alcohol, making it incredibly versatile. One of the most effective ways to distill this oil is using steam, but you can also place sprigs of rosemary in olive oil or vinegar to impart the flavor and some of the therapeutic benefits. Like all herbs, it is most potent when used fresh, but it can also be dried or frozen as well.

Other Activities & Resources

Check out a few of the tasks you can undertake in the kitchen garden right now, along with "recommended reading."

Read pages 55, 71, and 115 of The Maritime Pacific Northwest Gardening Guide from Tilth Alliance.
This month, there are several readings relevant to herbs in Plant, Grow, Harvest, Repeat by Meg McAndrews Cowden. Look specifically at pages 49, 78, 87, 124, 126, 194, 196, 219-221, 228, 236, 239, 246, and 259.
It's not too late to start small-seeded crops indoors. Check out our in-depth blog post on starting seeds to make sure you have all the supplies, and be sure to shop for seeds now for the greatest selection.
Check out Cynthia's interview with herbalist Amanda Lattin for an overview of aromatherapy with herbs!
If you're interested in learning more about herbalism, Basic Herbal Terminology is a blog post written by the education oriented folks at Mountain Rose Herbs. They define herbal terminology in an easy to read and learn format. Want to know more about herbal infusions? Salves? Teas? Tinctures? Essential oils? This blog post is worth a bookmark if you are getting started learning about herbs.
Loghouse Plants is one of our growers, and they have several well-researched medicinal herb profiles available that include information on growing these plants and their traditional medicinal uses.
Grow Your Own Herbal Remedies by Maria Noel Groves is a lovely book that provides plant profiles and instructions on how make and use herbal medicines to achieve wellness goals such as stress relief, relaxation, better sleep, improved digestion, detoxification, immune protection, improved respiration and pain relief.
If you already have some herbs growing in your garden, consider making a tea from one of your favorites with the help of our blog post on the subject.

April Planting

This year, April is shaping up to be cooler than in recent memory, but there's still plenty that can go in the ground this month — especially as we near May.

Look for bare-root perennial edibles like asparagus, rhubarb, and strawberries this time of year at the Farm.
Follow our guide for planting seed potatoes this month.
We have a fantastic selection of fruit trees, shrubs, and vines that have started to flower already. Look for apples, pears, persimmons, figs, blueberries, currants, raspberries, kiwis, pomegranates, and more.

Connect With Us

If you have questions about edible gardening or would like help selecting plants, our knowledgeable team is always happy to assist you in the Kitchen Garden Greenhouse. Cynthia often gives informal tours of our display beds, so feel free to stop by for a quick walk-around! For help from afar, you can reach out to Cynthia and our Kitchen Garden team directly at edibles@cornellfarms.com.

We are also excited to share that, for those wanting more individualized assistance with their kitchen gardens, Cynthia is also available for personalized 90-minute Garden Coaching Sessions held in your very own garden.