11 Tips For Growing Garden Herbs Indoors
Have you decided to grow herbs indoors this season? Many garden herbs can be grown indoors successfully with a little bit of patience and care. In this article, gardening expert and former organic farmer Logan Hailey shares her top tips for a thriving indoor herb garden!
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A thriving indoor herb garden doesn’t require a fancy hydroponic setup or a huge investment in grow lights. As long as you have a sunny windowsill, you can grow a surprising diversity of fragrant herbs right in your kitchen. Indoor herb gardens also serve dual purposes for culinary use as well as gorgeous decor to liven up any space.
When you start an indoor herb garden, there’s a few pitfalls you’ll want to avoid, and a few steps you can take to set your plants up for success. From herb selection to proper sunlight, there’s a number of factors to consider.
Indoor herbs are essential for apartment dwellers, home renters, cooking aficionados, and winter gardeners alike. These following tips will help you maximize your herbal harvests in a small indoor space.
Provide Adequate Lighting
The most obvious constraint for indoor gardeners is the roof over their heads. Most herbs need at least 6 hours of sunshine per day. Sunlight is a major limiting factor for indoor herb gardens, but there are plenty of ways to guarantee that your aromatic plants get the light they need.
First, work with the light you’ve got. Solar aspect is the angle of the sun at different parts of the day and year. Observe how the sun hits your house during different seasons and find the place where your plants can get the maximum amount of light.
The majority of herbs prefer the most open, south-facing window possible. This is especially important during the shorter, darker days of winter. Remove any awnings, curtains, branches, or other outdoor barriers that block sunlight from coming in.
If you don’t have a south-facing window, choose an east or west-facing window. Sometimes these are the best places for shade-tolerant herbs like thyme, mint, and parsley. This is especially the case if your house gets intense, hot sun rays during the summer.
However, If you want to grow basil or cilantro, be sure you have very bright, direct sunlight. These plants easily become weak and leggy in dimly lit windows.
If you don’t have any bright, sunny windows, all is not lost! You can always introduce supplemental lighting to fuel photosynthesis in your indoor plants.
Purchase an LED light from your local hardware store and hang it on a shelf or from the ceiling above your herb garden. Often, a combination of indirect natural light and direct artificial light creates the perfect ambiance for your herbs to thrive (while still looking nice).
Monitor The Temperature
Most herbs thrive at room temperatures around 70°F. However, windows often have a “microclimate” that is hotter or colder than the rest of the house.
Chilly drafts through uninsulated windows can harm cold-sensitive herbs like basil, lemon balm, and rosemary. Similarly, excessive warmth from the summer sun roasting on glass can cause problems with heat-sensitive herbs like cilantro and chives.
Place a thermometer near the windowsill and monitor temperature fluctuations to determine if you need to move your herbs closer or farther away from the window.
Choose The Right Herbs
The best herb varieties for windowsill kitchen gardens are compact and fast-growing. Perennials like rosemary and mint can easily be grown from cuttings or brought in via plant divisions from an outdoor garden.
Annual herbs like basil and parsley can be grown year-round as long as you prevent them from flowering and provide adequate warmth.
Herbs like dill, fennel, garlic, and chamomile are best kept outdoors because they need plenty of space to reach their fullest potential. Lavender can be grown indoors, but it prefers a larger pot than a standard kitchen windowsill garden.
If you are limited in space, we also recommend weighing the pros and cons of different herbs. For example, cilantro is a top pick because it wilts fairly quickly when you buy it from the store, and it has a wide variety of uses in the kitchen. Thyme, on the other hand, sustains a lot of its flavor when dried and is less delicate in storage.
Indoor Herb Care Guide by Species
Indoor Herbs | Special Care | How to Harvest |
Basil | Needs very bright light and warm temperatures | Pinch off the tips to encourage bushing and regrowth |
Chives | Prefer full sunshine and soil that is rich organic matter | Use scissors to cut down to the bottom 2-4” |
Cilantro | Needs bright light, or it will become leggy; dislikes intense heat | Pinch off leaves, pull side sprigs, or cut whole bundles |
Rosemary | Start with cuttings; prefers very well-drained, sandy or gravelly soil | Cut 2-4” long side stems or trim back up to two-thirds of the plant |
Thyme | Prefers drier soil and tolerates shadier windows | Cut 2-4” long side stems or trim back up to two-thirds of the plant |
Mint | Enjoys moist soil and tolerates shadier windows | Pinch off the tips or harvest whole branches |
Parsley | Start from nursery seedlings and grow in rich, moist soil | Cut individual stems from the base of the plant or pinch off leaf tips |
Oregano | Loves hot, sunny windows; prefers very well-drained, sandy or gravelly soil | Cut small handfuls or trim back up to two-thirds of the plant |
Sage | Likes medium to full sun and requires dry soil conditions | Pinch of leaves or snip small side sprigs |
Don’t Overwater Container Herbs
Overwatering is the most common mistake beginners make with indoor herb gardens. It’s easy to provide our herbs with a little too much love. Because these plants are rooted in smaller containers with less drainage than outdoor soil, they can easily succumb to root rot.
Infrequent, thorough watering is best. Always check the soil of your herbs before watering. If you stick your finger a few inches into the pot and it comes out clean, this indicates that your plant is ready for a drink. The soil should never feel soggy, heavy, or saturated.
When you water indoor herbs, don’t drown them with water. Use a watering can or a small-mouthed jar to irrigate gently. Allow the soil to absorb small amounts of water at a time. The water should not pool up on the surface or cause major soil displacement. Patiently distribute the moisture until water runs out of the drainage hole at the bottom of the container, then stop.
Remember, you can’t treat your entire indoor herb garden to the same watering schedule. Different species have different irrigation preferences.
For example, drought-tolerant herbs like rosemary and oregano need far less water than mint and basil. Typically, if a plant is drought-tolerant outside, that means it needs less water indoors as well.
Use this chart as a general guide but remember that water needs ultimately depend on the container size, temperature, humidity, soil type, and season.
Herb Irrigation Cheat Sheet
Prefer Moist Soil | Prefer Drier Soil |
Mint | Rosemary |
Chives | Oregano |
Basil | Thyme |
Cilantro | Lavender |
Chives | Sage |
Grow Each Species Separately
It may sound cute to mix and match several herbs in the same container, but we’ve found that the most successful indoor herbs are grown in separate pots. This allows you to cater to the specific needs of each plant. It also prevents more vigorous species from out-competing the others.
Choose Pots With Drainage Holes
There are lots of trendy pots and containers for herb gardens, but some of them aren’t designed for longevity. If you want your herbs to thrive, make sure you choose pots that have drainage holes. Old-fashioned terra cotta or ceramic pots with catchment trays are the best options.
Ideally, the drainage hole should be at least 1-2” in diameter. The water saucer should be deep and wide enough to hold about an inch of drained water without overflowing.
Some gardeners like to bottom-water into the catchment tray so the plant can drink up through its roots. This method only works if the drainage hole is large enough for the roots to reach through.
Use a Well-Drained Soil Mix
Drainage is a crucial theme for indoor container gardening. Without proper drainage, plant roots suffocate. While some plants can tolerate heavier clay or poorly drained outdoor soils, there is nowhere for water to go when it is clogged up inside a pot. Most of the problems with indoor plants can be alleviated by choosing a well-drained soil mix.
These herbs thrive with compost, worm castings, and potting soils that are rich in the organic matter:
- Mint
- Chives
- Parsley
- Cilantro
- Basil
Other herbs actually prefer poor soil that lets water pass through very quickly. These herbs don’t typically need compost or rich soil amendments.
Regardless of which herb species you choose, certain materials can be blended with your potting mix to improve water drainage and prevent root rot. These natural additives have a high porosity that allows water to pass through quickly. Our favorites include:
- Perlite or Vermiculate
- Horticultural sand
- Pea gravel
- Small stones (especially for Mediterranean natives)
- Peat moss
- Coco coir
- Sifted compost
- Shredded bark
Pay attention to the ingredients in your potting soil mix. If your herbs start to look droopy and yellow or have a foul smell coming from their roots, it’s time to dig up the plant and re-pot with a blend of better-aerated, fluffier materials.
Harvest to Promote Growth
Contrary to popular belief, regularly harvesting your herbs actually encourages more growth. It’s important to cut back old leaves and emerging flower buds so that the plant will generate fresh sprouts.
With tender annuals like basil and cilantro, I like to harvest by plucking leaf tips as I need them. This signals the plant to grow bushier and denser. It also prevents them from bolting (going to seed).
With perennial evergreen herbs like oregano and thyme, you can safely cut back up to two-thirds of the plant. At first glance, it may look like you’ve harmed the plant with such an intense haircut. In reality, this harvest method is like a pruning refresh. It triggers the plant to send up new leaves and stems.
Remember to only bulk-harvest your herbs during the active growing season. During the winter, it’s best to harvest smaller amounts because the plants grow back more slowly.
Start With Strong Seedlings
The easiest way to start an indoor garden is with robust herb seedlings from a reputable nursery or local farm. You can certainly use seeds or cuttings to establish your herbs, but it may take more time and attention.
For the quickest success, spend the extra few dollars to buy a healthy seedling and transplant it into your pots. If a seedling is too large for your container, you can always divide it by gently pulling apart the root ball and planting each half in a separate pot.
You can also bring herbs in from outdoor plants. Cuttings and root divisions allow you to get a head start on windowsill growing. However, be very careful not to introduce any pesky bugs or diseases into your indoor garden.
Thoroughly check the leaves for signs of aphids, whiteflies, or other pests. Inspect the roots for any signs of root rot, maggots, bad smells, or dark discoloration.
Use Slow-Release Organic Fertilizer
As a general rule of thumb, herbs do not need very much fertilizer. They aren’t nearly as hungry as garden vegetables and can even suffer if they are given too much fertilizer.
A small monthly dose of slow-release fertilizer is ideal for preventing yellow leaves or stunted growth from the lack of minerals in potting soil. Just remember— less is more when fertilizing herbs.
Choose organic fertilizers that slowly release nutrients into the soil. Our favorite fertilizers for indoor herbs include:
- Diluted seaweed or kelp fertilizer (great for micronutrients)
- High-quality compost
- Vermicompost (worm castings)
- Fish emulsion (in small quantities)
- Organic all-purpose granular fertilizer
Avoid fertilizing indoor herbs with synthetic nitrogen fertilizers. A large dose of quickly available nitrogen can actually cause your herbs to lose their signature aroma.
Lush annual herbs like basil and cilantro enjoy a spring and summer dose of fertilizer. Evergreen herbs like rosemary, oregano, and thyme typically require the least amount of fertilizer, if any at all.
Pay close attention to any signs of nutrient deficiencies (such as yellow leaves or stunted growth). Once you have ruled out the possibility of root rot or water issues, apply small doses of fertilizer and wait a couple of weeks to see how the plants respond.
Up-pot as Needed
Under the right conditions, indoor herbs can grow in great abundance. Sometimes they even overgrow their pots! When herbs start to get overcrowded, you need to prune and/or up-pot to maintain proper airflow.
Without aeration between leaves, fungal diseases can quickly take hold in an indoor environment without any wind. This is especially problematic in humid climates.
Depending on their vigor and your harvest schedule, indoor herbs need to be up-potted once or twice per year. All of the kitchen herbs we’ve mentioned here are tolerant of transplanting and don’t mind moving homes so long as you improve their soil with every transition.
Up-potting is also a great time to inspect the plant’s roots and prune off any dead or diseased plant parts.
A plant is considered “root bound” when its roots start to loop around the edges of the container and reach out of the drainage hole in a desperate search for more space. This is your cue to give the plant a larger home.
If you don’t have room for larger pots, you can always remove the root-bound plant from its pot, divide the root ball, and re-pot half of it as a gift to your chef or gardener friends. Your half of the herb can remain in its original pot and have plenty of room to stretch out in the season to come.
Final Thoughts
Whether you lack the space for an outdoor garden or you just want to keep your herbs closer to the kitchen, an indoor herb garden can thrive in any home or apartment. The keys to success are:
- Provide plenty of light: Most herbs need 6-8 hours of direct sunlight.
- Water thoroughly and infrequently: Don’t overwater – a good soak once a week is usually good.
- Focus on drainage: Use well-drained soil blends and containers with large drainage holes.
- Harvest regularly: Consistent harvests encourage your herbs to send out more growth.
If you follow these key care points as well as the tips listed above, you’ll have a thriving indoor herb garden in no time!