The primary reason for price fluctuation with essential oils is that the raw plant matter has different yields. The yield is measured by how much essential oil is obtained, on average, from a specific amount of planted crop (such as an acre).
An acre of orange trees would yield pounds and pounds more essential oil than an acre planted in lemon balm (Melissa), because oranges contain a large amount of oil in their peel. Lemon balm, on the other hand, is a plant that has high water content but a low amount of essential oil. Its yield per acre would be much lower. This is why Melissa oil costs approximately 100 times more than orange oil. This is an example of two vastly different plant yields. Many plants have similar oil content but not the same. In addition, conditions such as soil quality and weather will affect the yield of a crop from year to year.
Let’s take lavender as an example so that we can break down the numbers even further. Before moving onto to the lavender essential oil numbers, let’s talk about dried lavender so that you have a frame of reference for both. According to a report done by Washington State University (Washington is the number one grower of lavender in the United States) “an acre of Healthy, mature Lavandin Grosso plants should yield between 4 and 6 bundles per plant (bundles averaging about 150 stems per bundle). Assuming an average of 5 bundles per plant, and assuming a planting density of 2,400 plants per acre, a well-managed acre of Grosso should yield approximately 12,000 bundles. It takes between 12 and 15 dried bundles of Grosso to yield a pound of dried lavender buds. Another way to look at yield of dried buds is that one Grosso plant should yield between ¼ and ½ lb of dried buds. This equates to a little over 1,000 lbs of dried Grosso lavender buds per acre.”
Just a note: lavandin is a hybrid – a cross between true lavender and spike lavender.
Now, let’s see how much oil we can get from an acre of lavender. The above example is for a lavandin grosso, which usually yields twice as much oil as regular lavenders. The plants also grow larger which is why there are fewer planted per acre. That being said, since regular lavender is mainly what is used in aromatherapy, I’d like to focus on two varieties that yield approximately the same amount of oil – Provence and English.
According to another study done in Washington State, these two true lavenders yield about 25 pounds of oil per acre during a good crop year. This is at the high end of the spectrum, with 12 pounds being in the low range. However, for our purposes, let’s use the 25 pound figure. This weight is based on plants that are full-grown. Full-grown English lavender can be about 2 to 3 feet tall and approximately twice as wide. An acre of English lavender will hold around 2900 plants.
2900 plants divided by 25 equals 116. It takes 116 plants to make one pound of lavender essential oil. Most essential oils are sold in ½ ounce (15ml) bottles. There are 16 ounces in a pound. You can use a pound of oil to fill 32 of those ½ ounce bottles. So, 116 divided by 32 equals 3.625 plants. Rounding down to 3.5 to keep it simple, that means, inside each ½ ounce bottle of English lavender essential oil there are 3.5 lavender bushes that were originally 2 to 3 feet tall and 4 to 6 feet wide.
Can you image throwing three or four of these lavender bushes into your bathtub? For one thing, they wouldn’t fit. This is precisely why only a few drops of essential oil are needed whether it is for a bath, massage oil, or a small jar of cream. Most people don’t realize how potent essential oils really are. I hope that the above math demonstrates the strength of pure essential oils. A few drops are all you need. Period.