Basil comes in all different kinds, breeds, flavors, and scents. However, isn’t it jarring to have some basils smell like licorice or lemon while others smell like cat pee?
In general, basil plants can produce different scents akin to cat urine, lemon, licorice, or even cinnamon due to the presence of particular compounds like mercaptan, anethole, citral, cinnamate. Some of these compounds can be externally introduced while others are naturally produced by specific basil varieties.
There’s more to basil than the ones you grow in your garden or buy in the store. Basil varieties come in different smells, shapes, sizes, and geographies which determine their properties.
The reason why basil varieties differ in smell, taste, and even appearance is due to the particularly diverse nature of the genus Ocimum. Basil is able to cross-breed with different varieties to produce an equally vast number of offspring permutations.
We refer to these plant varieties selectively bred to have desirable properties as cultivars.
Looking at the numbers, there are around 50-150 species of basil in the world that are cultivars (specifically selected) of sweet basil (o. basilicum). There are other basil cultivars grown from other basil species as well.
The variety and versatility of basil make it possible to make a basil plant with a specific smell, taste, and other observable characteristics (phenotype) through selective breeding.
Why Does Basil Smell Like Cat Urine?
Basil smells like cat urine to some people due to the presence of mercaptan compounds in some basil species which are also present in cat urine (i.e. felinine).
Enzymes break down the mercaptan compounds present in basil, producing carbon dioxide, ammonia, and other mercaptan compounds. The ammonia and the sulfur-rich mercaptan compounds are attributable for the distinct smell of cat urine.
This compound is also present in other plants, in bad breath, flatulence, and even Sauv Blanc wine.
One reason could be that a cat is urinating on your basil plant. To know, look around or the soil of your plant. If this has been moved then probably is a cat. Take into account that you can also find feces on your soil. So, while inspecting, use gloves.
Boxwood basil, a variety of sweet basil, is often reported to smell like cat urine. Like many basil varieties, it has very tiny leaves and a strong odor to them. True to its name, this basil variety looks like a box and would look great in a kitchen or garden with its more symmetrical shape. This variety is reported to have been bred in France.
Gardeners recommend pruning basil or cutting off its flowers to remove or alleviate the smell.
If your basil smells like urine, it means that the problem is most likely genetic! It is also possible that the basil plant you are growing may not be of the culinary variety hence its odd smell.
The last reason could be that a cat possibly urinated on your basil plant. In this case, watering the soil under the plant to dissolve the ammonia.
However, be mindful, in this case, you cannot consume the basil. Indeed, both cat urine and feces (that might be on your plant even if not visible) can cause serious problems. If you find urine in your plant it is very likely that a cat is using your garden/pot as litter.
Basil smelling like licorice is normal. The smell of licorice is attributed to a chemical compound present in both licorice and anise known as anethole.
Anethole can be found in fennel as well. Certain basil varieties have this compound which gives them their distinct smell and flavor, often described as either like licorice and anise.
Thai, Licorice, and Anise basil are different plants but have similar characteristics such as their smell and tastes. These grow from 12-18 inches tall with long purple stems and purple flowers. The leaves are likewise small growing about 1-2 inches long.
The smell of lemon is basil is also normal. The chemical compound attributable to the lemon smell of certain basil varieties is Citral. Citral is composed of a mixture of neral and geranial and produces a distinct, pleasant lemon odor.
This chemical compound can be found in many plants such as the common lemon, lemongrass, lemon cypress, and lemon verbena. Many plants which have citral in them exhibit a yellowish hue on their leaves or stems.
Lemon basil (Ocimum x africanum, also known as Thai Lemon, Lao, or hoary basil) and its subvarieties are best known for their lemon smell and taste. This basil is a hybrid between the American basil (Ocimum americanum) and regular basil (ocimum basilicum). It’s available worldwide but mostly endemic to Asia and the Middle East.
Basil smelling like cinnamon is normal. The chemical compound attributable to the cinnamon smell of certain basil varieties is methyl cinnamate.
Methyl cinnamate is a white/transparent solid chemical substance which produces a strong, aromatic odor. It can be found in peppers, strawberries, and other culinary spices.
Mexican spice basil (also known as Cinnamon basil) is either a separate other cultivar or a cultivar of spice basil. Like thai basil, it has purplish stems however its leaves can get a bit longer and its flowers are pink.
How to Cross-Breed Basil
So we’ve got you interested in the dark arts of knowing the different basil varieties and now want to know how to grow your own basil. Lucky for you, YourIndoorHerbs has several articles ranging from growing to maintenance which you can find all over the site.
For growing basil, it is important to know that though they are easy to raise, it doesn’t mean you should neglect their needs. You need to prune them and make sure they are watered correctly. Soil should also be considered to make sure they grow healthy. Neglect may cause basil leaves to become transparent, or worse, die.
After this, you can move on to the process of cross-breeding.
First of all, basil is also self-pollinating which means that they can reproduce on their own without the assistance of another basil plant for fertilization. Basil is also a cross-pollinating protandrous plant. This means the stamens (male reproductive organ) develops before the stigma (female reproductive organ) becomes active.
The simplest way to cross-breed basil is to simply place two different basil varieties next to each other. The wind will naturally carry the pollen from one basil plant to the other, provided they are both flowering. This is not a sure-fire method as there might be a chance that the basil self-pollinated.
A more hands-on approach would be to manually clip the stamen from one basil plant and rub the pollen-rich stamen directly on the stigma of the other basil plant.
- Basil comes in all smells, tastes, shapes, and sizes. It is a versatile herb that can take on different characteristics through selective breeding.
- It is normal for basil to smell like lemon, cinnamon, and licorice. If your basil smells like cat urine, it may be due to the genetics of the basil plant.
- Basils are easy to grow plants and even easier to reproduce due to how versatile their genus is.
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