Guide to Growing Rosemary Indoors 

Published October 3, 2022
Plant of rosemary in pot and rosemary stalk in glass for rooting

Just imagine having round-the-clock access to rosemary's unique, aromatic scent (and taste!) in your home. Wouldn't it be wonderful? Not only is this a lovely idea, but the reality is well within your reach. Rosemary (Salvia rosmarinus) is a great herb to grow indoors. By following a few key growing tips, you'll easily be able to grow rosemary indoors year-round. Ready to get started?

How to Start Rosemary Plants to Grow Indoors

You can start rosemary from seed, but they take a very long time to germinate and start growing. If you're looking for a quick way to start growing rosemary indoors that doesn't require a trip to the garden center, it's best to start new plants from cuttings. This involves taking a few snips from an existing plant and rooting them in water or soil. If you don't have a rosemary plant, ask a friend to let you snip a few fronds. Rosemary is so prolific that they're sure to be happy to share.

Take Rosemary Cuttings

It's very easy to propagate cuttings from a rosemary plant, though it is important to know where to cut. Rosemary stems get hard and brittle toward the bottom; that portion of the stem will not propagate effectively. Look for the spot where the stem starts to get woody and be sure to snip above that point so that you get soft wood only. You can use garden snippers or even scissors to make the cut.

  • Each cutting you're going to root should be around six inches long.
  • If the stem you snip is long, cut it into pieces to get multiple cuttings.
  • Remove leaves (yum... use them in a recipe) from the bottom two (approximately) inches of each stem.

Root Rosemary Cuttings in Water

It is extremely easy to root rosemary cuttings in water. Just put a few inches of water in a glass or jar and place the rosemary stems in the water. The bottom portion of each stem should be submerged. Put the glass in a sunny window, ideally one within your daily line of sight. Dump the water each day (most days anyway... it's fine if you miss a few days here and there) and replace with fresh water. Keep an eye out for roots to form, which generally begin within two to four weeks. When the roots are a few inches long, your plant will be ready to transplant into a container.

Root Rosemary Cuttings in Soil

If you'd rather root your rosemary cuttings directly in soil, that's fine. With this option, you won't have to change the water every day, though you will need to keep the soil moist (but not soggy). Fill a small container that has drainage holes with a potting mix that drains well. Once your pot is situated, dip the bottom of each cutting in a rooting hormone powder, then place it in the soil. Water the soil thoroughly and place it in a window where it will receive six to eight hours of sunlight each day. Check the soil every few days; add water when the surface begins to feel even slightly dry. The cutting should develop roots within four to six weeks. Once it starts growing, transplant your rooted cutting to a larger container.

Moving an Outdoor Rosemary Plant Indoors

If you already have a potted rosemary plant growing outdoors that you'd like to move indoors for the winter, that is also a viable option. If you're going to do this, you'll need to take some time to get this heat-loving plant acclimated to the change of temperature and light it will face in a climate-controlled indoor environment. The best way to do this is to start moving your rosemary plant into a partially shaded area for a few hours each day, gradually increasing the amount of time it spends away from its ordinarily full-sun position. This will help it get used to a lower temperature and filtered sunlight. After a month or so of this, you can bring your plant inside. It's best to bring it in before temperatures dip below 50°F.

How to Grow Rosemary Indoors Like a Pro

Now that you have successfully rooted rosemary cuttings or brought an indoor plant inside, what comes next? Now the fun begins! It's time to start growing your indoor rosemary plant (or plants... why stop with just one?).

Indoor gardening. Women's hands taking care of herbs

Choose the Perfect Container

Choosing the right container will help set your rosemary plant up for success. If you have rooted a rosemary cutting, start by moving it to a terra cotta container that's about six to eight inches in diameter with a similar depth. You don't absolutely have to use terra cotta, but since rosemary's roots like to stay dry, terra cotta is particularly good for this herb. Once the herb gets taller than the container is deep, it'll be time to move it up to a larger pot. If you're growing a trailing rosemary variety or you want to keep an upright rosemary variety relatively short, opt for a maximum pot size of no more than 14 inches in diameter and depth. If you have brought an outdoor plant indoors, keep it in its original container unless you want to re-pot it.

Provide Plenty of Light

Rosemary needs a lot of sunlight, so it's a good idea to place your plant (or plants) in the sunniest window of your home. If you don't have a spot where they can get at least six to eight hours of direct sunlight (filtered through a window of course), you will need to use a grow light in order to provide these plants with the light they need. Don't assume that a spot that provides plenty of light during the summer will meet the plant's needs all year long. If you put your plant in a window that provides plenty of light during the summer, you still may need to provide additional artificial light during other times of the year.

Get Watering Just Right

Balance is the key to watering an indoor rosemary plant effectively. It's better to underwater a rosemary plant than to overwater it. The idea is to keep the soil from drying out completely, while also making sure that it isn't soggy at all. Indoor rosemary plants generally benefit from watering every two weeks (or so), but you should always check the soil before adding water. Only add water if the top inch or so of soil is dry. Consider keeping the container on a saucer filled with pebbles. This will help protect the roots from getting soggy (and rotting) due to moisture build-up in the container.

Keep Powdery Mildew at Bay

Powdery mildew isn't just an outdoor concern. Rosemary plants are prone to powdery mildew, even when grown indoors. To minimize the risk of powdery mildew, mist rosemary plants very sparingly, only during times when the air inside your home is extremely dry. It's also important to make sure that rosemary plants have plenty of air circulation. With that in mind, avoid placing rosemary plants so close to other plants that their stems or leaves may cross over or crowd each other. A lush multi-plant display might look nice at first, but crowding can lead to powdery mildew on rosemary plants.

Fertilize to Help Rosemary Thrive

Want to help your indoor rosemary plants thrive? Be sure to fertilize them properly. They don't need a lot of fertilizer, but rosemary plants do benefit from occasional feeding. It's a good idea to add slow-release fertilizer to your plant(s) each spring. You could either top dress the container with high-quality compost or feed it with any type of liquid fertilizer designed for indoor plants. Alternatively, you could fertilize it monthly during spring or summer with a fast-acting NPK fertilizer. If you have multiple houseplants, go with the option that you use for feeding your other plants so it'll be as easy as possible for you to keep up with when (and what) to feed your plants.

Is Rosemary a Good Indoor Plant?

With proper care, rosemary absolutely is a good indoor plant. In fact, it's one of the best herbs to grow indoors. The more you learn about planting, growing, and harvesting rosemary, the easier it will be to understand why it's a must-grow plant for every herb garden - indoors or outdoors. Whether rosemary will be the first herb you've grown inside or if you're adding it to an already-thriving indoor herb garden, you're sure to love having rosemary in your home.

Guide to Growing Rosemary Indoors