You might have noticed, perhaps with surprise, that whatever you do some herbs after one growing season, they will just die. This is not your fault, it is just how mother nature works. However, before starting nurturing any herb, you need to know how long it lasts, so to have a realistic expectation of your eventual workload. This article has analyzed more than 30 common indoor herbs providing all the information you need on their lifespan.
Hence, how long do indoor herbs last? Among the most common herbs, some are annuals as the following ones:
There are also hardy perennials that live for many years in the right conditions. Among the most common, there are:
This is only a list of the very common ones. Further, you can find a complete list also for the least common herbs. However, you know that some herbs can last more than they should in the right conditions? Keep reading to learn more.
Herbs can be classified as either annual, perennial, or biennial in function on how long they last.
Annual herbs only last one season. This is how they are genetically programmed. Independently on how well you water or provide lights and nutrients (not always necessary, more in this fertilization guide), and sometimes, depending on the plant and the conditions, may only live up to four months before going to seed and die. This usually happens in the coldest season.
Perennial herbs last many years (more than two). During the cold season (if the temperature does not drop too much), they will either stay green or, more often than not, will go in a particular state called dormancy. This is a biological defense through which, by slowing down their growth (and so need for light and nutrients) they can survive through a harsh (but not too much) winter. If you are interested in the scientific part of it, have a read to this publication from the Swedish University of agricultural science.
Between the two extremes, we have the so-called biennial herbs such as Parsley and Chervil. Biennials herbs last about two years before they stop production, go to seed, and die. Here is a list of the most common annual and perennial herbs as detailed discussed by Penn Extension Institute and Professor Longbreak.
Annual and Biennial Herbs
|Angelica||Biennial||Partial shade||Grow indoors in cooler climates|
|Basil||Annual||Protected sun||Easy to grow indoors|
|Borage||Annual||Full sun||May need grow lights for best results|
|Calendula||Annual||Full sun or partial shade||May need grow lights for best results|
|Caraway||Annual||Full sun||Not suited due to size (60cm) and light needs|
|Chervil||Biennial||Partial shade||Easy to grow indoors|
|Clary Sage||Biennial||Full sun||May need grow lights for best results|
|Annual||Full sun or partial shade||Suitable to grow indoors|
|Dill||Annual||Sun or partial shade||May need grow lights for best results|
|Edible Watercress||Annual||Shade||Suitable to grow indoors|
|Endive||Annual||Full Sun||May need grow lights for best results|
|Fennel||Biennial||Full sun||Not recommended to grow indoors|
|Parsley||Biennial||Full sun or partial shade||Easy to grow indoors|
|Summer Savoury||Annual||Full sun||May need grow lights for best results|
|Sweet Chamomile||Annual||Full sun or partial shade||Suitable to grow indoors|
|Anise||Full sun or partial shade||Suitable to grow indoors|
|Bee Balm (Bergamot)||Full sun or partial shade||Petit variety only suited to grow indoors|
|Catnip||Full sun or partial shade||Suitable to grow indoors|
|Chives||Full sun or partial shade||Easy to grow indoors|
|Feverfew||Full sun or partial shade||Suitable to grow indoors|
|Horehound||Full sun||Suitable to grow indoors|
|Lavender||Full sun||May require grow lights for best results|
|Lemon Balm||Full sun||Suitable to grow indoors|
|Lemon Verbena||Full sun||Suitable to grow indoors|
|Lovage||Full sun or part shade||Not suited to grow indoors because of large roots|
|Oregano||Full sun||Suitable to grow indoors|
|Peppermint||Full sun or part shade||Suitable to grow indoors|
|Pineapple sage||Full sun||May need grow lights for best results|
|Rosemary||Full sun||May need grow lights for best results|
|Sage||Full sun||May need grow lights for best results|
|Salad Burnett||Full sun||Suitable to grow indoors|
|Scented Geranium||Full sun||Suitable to grow indoors|
|Southernwood||Full sun||Not suited to grow indoors because of the size|
|Sweet Marjoram||Full sun||Suitable to grow indoors|
|Tarragon||Full sun||Suitable to grow indoors|
|Thyme||Full sun||Easy to grow indoors|
However, you need to know that environmental conditions (temperature and sunlight, especially) impact the herb lifespan. For example, cilantro (also known as Coriander) is classified as a biennial herb. Still, in warmer climates, it can begin to seed in just a few months as discussed by a 30-years experienced gardener from Florida here.
The opposite is the case for chives. They are perennial, but if the winter temperature drops too much, they will die, making them annual herbs. This can also happen for any of the herbs. For example, you may experience shorter annual lifespans for herbs that, in general, are perennial such as mint, dill, arugula. The warmer conditions may stimulate the seeding cycle earlier than expected.
In contrast, those herbs that enjoy dryer conditions (such as Rosemary, Oregano, Marjoram, Sages, Thyme and Tarragon) can be expected to last several years in the warmer climates before going to seed. Experienced gardeners have had Sage plants last for up to three years with the proper conditions and care as detailed here.
You Want Your Herbs To Live Longer? Here my 3 Tips
To get the most out of your indoor herbs, it is vital to give the proper care and attention to the type of plant. The most critical factors to prolong the life of your herbs is light, watering, feeding, and pruning.
Most herbs need around 6 to 8 hours of sunlight each day. If they don’t get it, their stems will become long and weak, a process called etiolation, and eventually die (for more here). Hence, a perennial might not survive during winter (making it an annual) due to the lack of fo the right environmental conditions.
So make sure you choose the location for your herbs that get the most sun during the day, ideally a sun oriented windowsill. The right amount of sunlight also helps in releasing the natural oils, which makes your herbs smell and taste great (here a detailed guide of the best smelling indoor herbs).
Tip 1: If you are not able to get the right amount of light naturally in your home, you do not need to give up! You can supplement what is missing with cheap grow light (here a grow light guide for beginners). Indeed, you need to know that herbs do not differentiate between sunlight or artificial light. Both can provide the same benefits. It is essential, though, to choose a plant-designed light. The other option is to select herbs that grow better in the shade, such as Parsley, Thyme, and Chives. You can also grow herbs in your basement with the right light, as also shown in this step by step guide to your basement garden.
One of the most common mistakes new gardeners make is overwatering their indoor herbs. This will indeed create the right environment for the root rot bacteria to develop and kill your herb. In fact, most herbs need a lot less water than you think. Those plants that like more moist conditions can be watered more generously (for example, mint, parsley, and cilantro).
Tip 2: to avoid overwatering, just stick your finger (or a toothpick) and check the moisture of the soil. Does the soil stick to your finger? Hence, it is already wet enough. Do you feel it dry? Hence, probably it is! Remember always better underwatering than overwatering. For more, just have a look at those 21 tips to grow massive basil, applicable to the majority of herbs.
Fertilizing the herbs, especially the softer ones, will keep them happy and healthy. Make sure that the fertilizer you use is food safe though if you intend to use these herbs in your cooking as claimed by expert gardeners here. Read the care guide for the herbs you have to get more information on their feeding requirements and remember to avoid the most common mistake: overfertilizing.
Tip 3: if your herbs look green and robust, you do not need fertilizer. Remember, if you use good quality potting soil, very likely it contains fertilizer (just read the package) that can last more than half a year. For more, have a look at this detailed fertilization guide for indoor herbs.
Tip 4: pruning and harvesting is really the key to a longer life. Indeed, this encourages new growth by promoting the production of growth hormone in the herb. This is the real game-changer if you want to extend the lifespan of your herbs. But don’t leave a bare stem with no leaves. You need to know how to cut your herbs.
In short, you need to cut the stem above the node. This is the real trick to stimulate massive growth! For more, have a look at this propagation guide with pictures, that will guide you on how the herbs need to be cut. For the hardier herbs such as oregano and time, let them grow into a decent sized bush, then you can prune the branches.
For your biennial and perennial herbs, they will not need much care over the winter months. Let them in the dormant state to then come back to life for another great growing year ahead as discussed by expert gardeners here.
The Most Convenient Herbs To Grow?
The convenience of an indoor herb is measured by how long it lasts (the longer, the better), how easy it is to grow, and how often it can be used in your meals. Against these measures, in my personal opinion, the most useful herb to grow indoors is parsley for the following reasons:
- Duration: as we saw before parsley is a perennial, so it can last many years if in the right light, temperature and soil water moisture conditions;
- Light: While parsley can grow in full sun, shade is better to create a vast stock of lush leaves, so you don’t have to be so concerned with its location in the house (here a guide on the herb that does not need full sun). If you are growing from seed, it also yields quickly with your first leaves ready in just about three to four weeks. It is also a biennial herb, so under the right conditions, it should last around two years;
- Cooking: Parsley is also chosen as the most convenient indoor herb because of its versatility in cooking. Parsley is a subtle flavor and can be used in all varieties of cuisines, from the Mediterranean to Asian. Here a glance to 40 recipes (but there are many more) that use this herb.
Thyme, mint, and chives are also very convenient herbs to grow. They don’t require much light and grow rapidly. They are also either biennial or perennial herbs, which means they should have a lifespan of several years. The drawback with these herbs is their quite intense flavor that might not be suitable for all taste and limits their culinary use.
Do herbs grow every year? Perennial do not need any action from the gardener. On the other hand annual herbs (like sweet basil) require the owner to cut back the whole plant once gone to seeds and let the new plants (from the seeds) to grow.
Is spearmint a perennial? Yes, this is a perennial, given that the winter temperature does not drop below 20F (-7C) below which the herb and roots will die with no chances for the mint to grow back when the warmer season starts.
The collage photo that will hopefully help you in better identifying herbs by their lifespan would it was possible only with the contribution from the following photographer (all with free to use and modify license)
- Angelica – https://www.flickr.com/photos/arripay/14235011128/sizes/l/
- Anise -https://www.flickr.com/photos/cynren/6853854201/sizes/o/
- Borage – https://www.flickr.com/photos/matsuyuki/425096560/sizes/l/
- Calendula – https://www.flickr.com/photos/radu_chibzii/48060867837/sizes/o/
- Caraway – https://www.flickr.com/photos/stanzebla/42889093292/sizes/l/
- Chervil – https://www.flickr.com/photos/edsel_/3497853296/sizes/l/
- Clary Sage – https://www.flickr.com/photos/33037982@N04/7170750753/sizes/o/
- Cilantro – https://www.flickr.com/photos/dasqfamily/2648343226/sizes/l/
- Dill – https://www.flickr.com/photos/gwennseemel/8456678922/sizes/o/
- WaterCress – https://www.flickr.com/photos/healthaliciousness/5548569758/sizes/l/
- Endive -https://www.flickr.com/photos/10873597@N00/14752297893/sizes/l/
- Fennel – https://www.flickr.com/photos/jorgezapico/14296968129/sizes/l/
- Parsley – https://www.flickr.com/photos/dinesarasota/3586142199/sizes/l/
- Summer Savoury – https://www.flickr.com/photos/145468477@N06/37156516160/sizes/l/
- Bergamot -https://www.flickr.com/photos/ruthanddave/196231358/sizes/l/
- CAtnip – https://www.flickr.com/photos/aligraney/660863109/sizes/l/
- Chives – https://www.flickr.com/photos/mbowler/540413248/sizes/l/
- Feverfew – https://www.flickr.com/photos/swallowtailgardenseeds/27370408870/sizes/l/
- Horehound – https://www.flickr.com/photos/dionysia/134627586/sizes/o/
- Lemon Balm – https://www.flickr.com/photos/alicehenneman/5851264304/sizes/l/
- Lemon Verbena – https://www.flickr.com/photos/starr-environmental/24514839084/sizes/l/
- Lovage – https://www.flickr.com/photos/aroberts/26780197241/sizes/l/
- Pineapple sage – https://www.flickr.com/photos/50228879@N00/6101363505/sizes/l/
- Salad Burnett – https://www.flickr.com/photos/macleaygrassman/31165481453/sizes/l/
- Southernwood – https://www.flickr.com/photos/zharkikh/7601900490/sizes/l/
- Sweet Majorana – https://www.flickr.com/photos/starr-environmental/25294870055/sizes/l