Editor's Note: We are thrilled to welcome Katie Stemp and Kellie Phelan, co-owners of Seattle Farm School, to our blog! Katie, Seattle Farm School's founder, is giving us all the info we need to successfully grow herbs indoors. With cold weather moving in this weekend, we're excited for an indoor gardening project (and recipes for scrumptious herb-focused snacks). Learn more about Katie and Kellie at the end of this post.
Time required: 30 minutes once all materials are collected
- Herbs of your choice
- Pots or containers made of metal, plastic or ceramic with drainage holes
- Tray or plate for under the container
- Good quality container soil mix, preferably organic
- Paper towel or coffee filter to cover drainage hole
- Grow lamp (optional for low sunlight locations)
- Fertilizer (fish emulsion, seaweed, or other herb-specific organic fertilizer)
Growing herbs indoors is easy! If their basic needs are met, such as good soil, adequate light
and the right amount of water, herbs will reward you with gorgeous plants and flavorful meals all year round. If you are new to indoor gardening or cooking with fresh herbs, these basic instructions will get you started.
The first question to ask yourself when planning your indoor herb garden is what herbs do you like to cook with? If you have never used fresh herbs before, examine your spice rack and choose herbs that you frequently use in their dried form. Start with 3-5 favorites! A few herbs that grow well indoors are thyme, mint, rosemary, chives, and parsley.
Many herbs have similar light requirements and can be grown together in a large container, or separately in smaller pots. Mint is an aggressive grower and is best grown in its own pot. Grouping herbs with similar watering needs can help your plants thrive: rosemary, thyme, and sage need less water than herbs such as chives, parsley, mint, and cilantro.
We suggest starting with small herb plants you can get at a nursery for most of your indoor garden. Choose herbs that have good color, strong stems, no damage or signs of disease (yellow or browning leaves or mold growing on top of the soil). If you would like to try starting your herbs from seed you could easily grow basil or cilantro quickly. Bill Thorness, a local gardener and author, did a nice seed starting post on Swansons' blog.
For an herb to be useful in the long term, it will need room to grow. Choose a container that will provide at least 8 square inches of space per herb to avoid overcrowding. Good air circulation will help keep the leaves dry, which will help prevent disease.
Containers made of plastic, metal or ceramic are all good choices as long as they have drainage holes at the bottom. You can cut, drill, or pound drainage holes if needed depending
on the container material. For the purpose of growing smaller herbs indoors, terracotta
pots tend to dry out too quickly, making it hard to keep the soil at the correct moisture level.
Don’t forget a tray or plate to put underneath your container to keep extra water from escaping.
Buy a good quality soil mix made specifically for container gardening, preferably an organic version. It will help maintain the correct soil moisture level for your plant. Don’t use soil from your garden outside - it’s too heavy and usually filled with weed seeds. A nursery associate can guide you to the right product for your needs.
If your desired herb garden location does not get at least 6 hours of direct sunlight every day, you will want to add artificial light to keep your plants growing well. My kitchen has a large window above the counter but it faces north and gets no direct sunlight so I have added an LED grow lamp on a timer to keep my herbs healthy.
At home, transplant your herbs from their nursery pots to your indoor containers. On the inside of your chosen container, cover the drainage hole with a paper towel, coffee filter or plastic screening to keep soil in and let extra water out. Fill the container three-quarters of the way with the container soil mix, making a hole where the new plant will go.
Avoid damaging your herb by not pulling the plant out of the pot by its stem. Instead, take your herb out of its nursery pot by softly squeezing the outside of the container to loosen the plant from the pot, then place your hand at the base of the plant positioning the plant stem between your thumb and pointer finger. Turn the pot over and remove the herb from the pot. With your other hand, loosen the roots and place it in the new container. If the roots are too long and rootbound in the pot, you can cut off the very bottom of the roots to allow room for growth into the new soil.
Fill around the plant with more soil until its level with the original soil level from the nursery pot. Water around the plant to get rid of air holes in the pot, and top off with more soil if needed. Your soil level should be just below the rim of the container.
A good rule of thumb for container herbs is to water only when the surface starts to dry out. Stick a finger into the soil and if it’s dry up to your knuckle (or an inch below the surface), it’s time to water. You want the soil to be damp like a sponge that has been squeezed out, not soaking wet.
Turn your containers weekly so both sides of the plants get adequate sunlight. Adjust supplemental grow lamp time based on how well your plants are growing or not growing. If they start looking “leggy” and get long stems with few leaves that look like they are stretching up for more sunlight, it’s a sign that your plant is not thriving and needs more light. If sunshine is not available, or we have long periods of gray overcast weather, provide additional light for up to 12 hours per day, with the grow lamp bulb 6 inches above the top of the herb. Note that no matter what, a plant grown indoors will most likely grow slower than those grown in the ground or large containers outside.
Keep the climate stable and containers away from cold, drafty areas of your home. An indoor temperature between 60-75 degrees is perfect. You can always move your herb plants outside in the summer and back inside for the winter.
All indoor herbs benefit from occasional feeding with an all-purpose water-soluble
fertilizer. Fish emulsion or seaweed can also be used. In general, fertilize herbs every 2 weeks and follow the instructions based on the fertilizer type. Only feed plants when they are actively growing and do not over-fertilize. Too much fertilizer may kill the herb plants.
Pruning & Harvesting
Prune for strong growth. Your herbs will grow best if you regularly prune and harvest from
them for good growth. Always cut sprigs, not individual leaves. On woody herbs like thyme,
rosemary, mint, and sage, either pinch or cut with scissors on the stem above a set of leaves to
encourage new branches to grow from the leaves you left behind. This type of pruning will
create a strong, multi-branched herb that will produce more than if you just picked the leaves
only. On soft-stemmed herbs like parsley, cut from the outer leaves and new ones will grow from the center. For chives, cut at the base of the stem.
All plants will eventually flower as part of their life cycle, but pruning to delay this inevitability will give you a longer harvest. Once a plant starts to flower, the flavor becomes more bitter.
Many herbs will go dormant for part of the year and die back before regrowing. Don’t worry if you experience this at home, it’s perfectly normal! They need to hibernate for a while to regain strength and energy for the next growing season. Chives and other soft-stemmed herbs will do this more than woody herbs like rosemary or thyme.
Diseases & Pests
The most common way to kill an indoor herb is to overwater and rot the roots. If your herbs have good air circulation, are not getting too much water, and you are continuously pruning and harvesting from them, they will stay much healthier. If you do find signs of disease or plant weakness (leaves that are yellowing, mold growing around the base of the plant, or bugs attacking) be sure to isolate the plant from the others so that it doesn’t spread. Check the roots to make sure they are white, strong and healthy (not brown and dry or gray and mushy) and remove the affected parts of the plant or root then repot in new soil.
Cooking with Herbs
Now let’s talk about using your herbs! This is the fun part! Your diligent care will be rewarded
with gorgeous fresh herbs that add flavor, dimension, and fun to your meals and drinks. You can add herbs to just about anything - sauces, baked goods, salads, pizzas, cheese plates, drinks, even desserts!
Here are a few of our favorite recipes from our upcoming book The Happy Hour Garden, due
out in early 2019.
Lemon Thyme Cocktail
In a shaker filled with ice add:
4 oz vodka
1.5 oz thyme simple syrup
1.5 oz fresh squeezed lemon juice (approximately the juice of 1 lemon)
Shake vigorously and pour into two chilled cocktail glasses. Garnish with a slice of lemon and a sprig of thyme.
Thyme simple syrup:
In a small saucepan combine:
20 coarsely chopped thyme sprigs
1 cup of sugar
1 cup of water
Heat until sugar is dissolved. Let cool, strain, and store in a glass jar in the fridge for up to 3 weeks.
Herb Crackers with Herb Goat Cheese
In a large mixing bowl combine:
2 cups all-purpose flour
3 tablespoons coarsely chopped fresh herbs, such as thyme or rosemary
1.5 teaspoons kosher salt
1 teaspoon sugar
Mix well, then add:
3 tablespoons cold unsalted butter pieces (it works well to grate on a cheese grater)
1 cup heavy cream
Mix until soft, smooth dough forms. Divide into 4 sections, wrap in plastic and chill for 30
minutes or up to several days. Heat oven to 375. Roll out one dough ball as thin and evenly
as you can on well-floured parchment paper or a silicone mat and score with a pizza cutter into 2” squares. Brush top with 2 tablespoons of melted unsalted butter and lightly sprinkle with sea salt. Transfer parchment paper to a baking sheet. Bake until dark golden brown* (18-22 mins). Cool completely. Repeat with remaining dough.
Tip: If the crackers don’t bake all the way until dark golden brown, they will have too much
moisture to be crispy.
Herb Goat Cheese:
Coarsely chop a variety of fresh herbs and edible flowers such as thyme, parsley, sage, chives,
oregano, violas, calendula and borage petals. Spread chopped herbs and flowers on a large
piece of plastic wrap approximately the length of a goat cheese log and 3 times the width.
Sprinkle with flake sea salt and freshly ground pepper. Place the goat cheese log at one end
of the herbs and using the plastic wrap as a guide, roll and lightly press the goat cheese into the herbs. Keep wrapped in plastic and chilled until ready for use. Remove plastic wrap, cut into slices and arrange on a platter or board alongside herb crackers and other cheese plate
Here is a handy cheat sheet with recipes and herb care:
About the Authors
Katie Stemp is the founder of Seattle Farm School, with a mission of growing a strong,
sustainable and self-sufficient community through teaching hands-on skills in fun urban
homesteading workshops. Katie, and Farm School co-owner Kellie Phelan, are currently writing a book called The Happy Hour Garden on how to use homegrown herbs and produce to create
delicious cocktails and appetizers. They hope you will join the fun at one of their Happy Hour
Garden classes this year! You can find a full list of their workshops at www.SeattleFarmSchool.com.
Seattle Farm School is coming to Swansons with a free seminar on growing herbs! Info will be posted soon on Swansons' What's Happening page.