Growing Herbs

herbs in a hanging basket

Growing your own herbs is a lot of fun that brings a lot of fulfillment.

In this guide, we’ll cover what you need to know to grow your own herbs.

Planting herbs seeds

If you are starting your herbs from seed, the timing of your planting will be a bit different than if you purchase an herb plant from the store.

Aim to plant the seeds with enough time for them to germinate, sprout and mature before you plant them outside. For most herbs, it’ll take 2 to 4 weeks for the seed to germinate, and a few additional weeks before they are OK to be planted outside.

To plant the herb seeds, purchase some potting soil and fill a container or tray with the potting soil. It doesn’t have to be a deep container — even a shallow tray will be fine for herb seeds. 

You can purchase plastic pots or packs to plant them, or use something you have lying around your home, such as an egg carton.

Once the container is full of potting soil, poke a hole in the soil with your finger no deeper than the first joint in your finger. Then, place the herb seed in the hole and cover it up lightly with potting soil.

To initiate the seed’s growth, water the herb seed lightly.

Try to keep the soil in direct sunlight as much as possible. You can cover it with some clear plastic to keep the humidity high as well. 

Make sure to keep on watering the soil lightly whenever it dries out. The soil doesn’t need to be more than damp, but it does need to be moist consistently for the herb seed to germinate.

You’ll soon start seeing a baby herb sprout emerging from the potting soil.

Transplanting herbs seedlings

After the herb sprouts, you’ll want to let it grow a little bit to establish a root structure. If the seedling is planted with its own space to grow, you won’t need to transplant it until it grows its own root cube. 

However, if the herb seed was planted with other herb seeds in its own space, it should be planted earlier so that its roots aren’t in competition for limited space.

As long as the roots have room to grow, you’re fine to keep the herb in its container. 

If you notice that the herb seedling is drying up fast, this may be a sign that it’s time to plant it in a larger container. You can transplant a herb however many times you’d like before planting it in its final destination.

To transplant a herb, pinch the bottom of the container as you gently pull the sprout up. If the seedling is very small, you can turn the pack upside down as you do this for each sprout so that the plant and its early root structure fall out into your hand. 

If the herb is rootbound, meaning that the roots are tightly wound together forming the shape of whatever container it was in, then you’ll want to gently rip the roots apart once before transplanting the herb into its next container.

After you have transplanted your herb, water it in and make sure it gets some sunlight for continual growth.

Planting herbs outside

Whether you are growing your herb from seed, or you purchased a young herb plant from a local garden center or greenhouse, eventually you may want to grow it outside.

Herbs can be grown inside, but they will flourish more outside.

To plant your herb, gently squeeze the bottom of the container and pull the plant out of its pack.

Then, use a trowel or your hand to remove soil from where you’d like to plant it. 

If the soil is hard and packed down, consider using a tiller to break it up, or just push a shovel in the soil a few times to break up the clumps.

Best soil type for herbs

You can check your herb plant’s tag for specific information regarding soil needs.

You may need to mix in some potting soil or other soil additives to get your soil to the ideal consistency.

When to plant herbs outside

Choosing when to plant herbs outside is an important consideration. If you plant them too early, there’s the risk of a late frost killing them off.

As a general rule of thumb, typically if you wait until after Mother’s Day you’ll be fine to plant herbs outside. That being said, in Central PA we have had late frosts later than Mother’s Day, so make sure to check the forecast for your area in the spring to make sure that there isn’t a deep frost on the horizon.

In some cases, planting herbs outside before Mother’s Day is definitely doable. Some annuals are just hardier than others, so you’ll want to consider the hardiness of your herb, too.

It depends on the plant’s size, maturity, hardiness (did the greenhouse you purchased the plant from “harden it off”?), and spring weather.

Where to plant herbs

Once you have your herb, you’ll need some soil and a spot to plant it. If you’re going to be planting it directly outside from the pack you purchased it in, you have the option of planting the herb in the landscape, in a hanging basket, or in a pot. A herb will do great in any of these locations.

Sunlight requirements for herbs

If your herb receives too little or too much sunlight exposure, it will likely still live, but may not grow as abundantly and could require more care.

There are general sunlight requirements for all herbs. For specific sunlight requirements for the variety of herbs that you purchased, make sure to check the plant tag.

Best temperature and humidity for herbs

Most areas have plenty of temperature swings, so an easy way to determine if your growing area will work for herbs is to check your USDA growing zone.

A herb will grow well in most USDA growing zones, but the length of its season will vary depending on the region.

Watering herbs

One of the most important factors to keeping your herb looking healthy is to diligently water the herb plant throughout the summer. 

For herbs, you’ll know they need water when the top inch of soil is dried out. To check, you can stick your finger into the soil down to the first joint in your finger. If it’s moist, no need to water the herb plant. If it’s dry, you’ll want to water it in.

Be careful that you don’t overwater the herb. A herb plant can be susceptible to diseases if it gets too much water. 

If you planted the herb in a container, make sure that it has holes in the bottom for excess water to escape. Otherwise, the water can collect at the bottom of the container and cause root rot, or other diseases.

Fertilizing herbs

Another important factor for plant health is keeping your herb fed with nutrition.

If the herb is planted in the ground, you can lessen the amount of fertilizer it’ll need by building up the soil with compostable material in the year(s) leading up to your planting. Otherwise, you’ll want to fertilize the herb throughout the summer. 

A good rule of thumb for fertilizing herbs is to give the plant a water-soluble fertilizer every third watering. This rule helps to account for the change in temperature and weather throughout the season. For example, in May you won’t be watering your herb plant as much as in the heat of the summer in August. So feeding the plant every third watering helps to provide the herb plant what it needs throughout the season, no matter the weather conditions.

It’s also recommended to plant the herb with a slow-release form of fertilizer to feed the plant slowly throughout the summer. You can add this in with your potting soil in a pot.

Growing herbs in a hanging basket

If you’re growing herbs in a hanging basket, you’ll want to make sure you don’t overfill the basket with plants. Plants will generally fill in the space you give them, so if the hanging basket isn’t packed full when you first plant it, that’s great.

The more herbs you plant in your hanging basket, the more you’ll need to water the hanging plants. In general, if more plants compete for water and soil, it’ll take more maintenance to keep the hanging basket looking beautiful.

If you’re watering your herbs in a hanging basket, you can check if it needs water by lifting the basket from beneath. If the basket is noticeably light, it could use some water. 

You’ll know you overwatered your herb in a hanging basket if water comes dripping or streaming out the bottom of the basket where the holes are.

Growing herbs in a pot

As mentioned above, be careful you don’t plant too many herbs in a flower pot.

The answer for how to care for herbs grown in a pot will vary according to the size of the pot. In general, make sure that it has plenty of room to grow and has adequate sunlight exposure where the pot is placed.

A herb that is planted in a container, whether it’s a pot or a hanging basket, will need to be watered more than herbs that are grown in the landscape, since they won’t be able to pull natural water from the ground.

Growing herbs in the landscape

Choosing herbs for your flower beds or other landscaping is a great choice. They make for great borders and can help add beauty to your yard.

Since you’re planting them in a permanent spot, you’ll want to be extra careful when planting herbs in the ground outside. Ensure that there’s little chance of frost and that the herbs are in a spot that matches their sunlight needs.

If you do have a late frost, and your herbs are already in the ground, you can cover them overnight with a bucket or sheet to protect them in most cases.

Do herbs bloom?

Most times, you don’t want herbs to bloom. Typically a blooming herb indicates that the plant is “going to seed,” or in other words, reaching the end of its lifespan.

Pruning herbs

Cutting back or pruning your herb can be healthy for the plant. You shouldn’t need to do this more than a few times throughout the summer. It can be good to do this if the plant is overgrowing its area or overpowering another plant in a container.

Common diseases for herbs

A herb is more susceptible to common diseases, such as downy mildew or root rot when it isn’t cared for properly. That being said, even herbs that are given the correct care can fall victim to some diseases.

Consult with your local garden center if you notice that your herbs have a disease.

Overwintering herbs

Most herbs can be overwintered, especially if you live in a warmer climate.

In Pennsylvania, herb plants like thyme and rosemary will die off if left outside during a harsh winter. But even just a few hours south in Virginia, residents can grow their rosemary bushes through the winter.

It really comes down to what growing zone you live in. I grow plants in the PA growing zone, so most herbs should not be kept outside if you’d like to use them in the spring.

Pest control for herbs

Typically, natural predators are enough to take care of bugs and pests that eat your herbs. For example, ladybugs will eat aphids and can help control them.

However, in some cases, you will need to take extra measures to kill off plant pests. Again, consult with your local garden center for a specific solution to your pests.

Companion plants for herbs

There are many other plants that grow great with herbs. These are what we would call “companion plants.” This means that if they are planted together they will generally complement each other with their colors and growing styles.

When looking for companion plants for your herbs, look for plants that have similar growing needs. This is an easy way to find plants that grow well. For example, if two plants love the sun, require similar fertilizer needs and one is taller while the other is a spreader, they will probably be great companion plants in a pot or hanging basket.

Varieties of herbs

There are many varieties of herbs. In general, their growing needs will be consistent across these varieties, but it’s always best to check the plant’s tag to make sure there aren’t specific instructions for your variety of herbs.

Propagating herbs

It’s possible to propagate herbs. 

To do so, you can cut off a small piece of the plant and put it in water for a week or so. Soon, the herb should start growing fine roots.

Eventually, you’ll be able to plant the herb cutting into the soil.

For some varieties of herbs, propagating and then selling your cuttings as plants once they are established is illegal. Make sure there isn’t a patent on the herb variety before you would do this.

Some annuals, such as sun coleus, can be propagated just by placing the cutting directly in potting soil.