the aromaconnection blog

Increasing Geranium EO Yield

A South African study published in HortScience suggests that essential oil yield in Rose-scented Geranium (Pelargonium capitatum x P. radens) is increased by frequent irrigation and brief water stress before harvest. (h/t Herb Companion.)

The experiment was conducted on geraniums growing in pots, using varying irrigation frequencies. From the abstract:

Both herbage yield and essential oil yield positively responded to frequent irrigation. Thus, higher herbage and essential oil yields were obtained from the highest irrigation frequency.

A one week stress period of withholding irrigation just before harvest was found to significantly increase total essential oil content as well as oil content per fresh herbage weight. Interestingly, the stress period modified the chemical content:

Citronellol and citronellyl formate tended to increase with an increase in the stress level, but the reverse was true for geraniol and geranyl formate. Other major essential oil components were unaffected by water stress.

Published in HortScience 43: 286-583 (2008)

For more information on the cultivation of Rose Geranium, visit the BioAfrica Plant Profile.

Technorati Tags: rose geranium,citronellol,citronellyl formate,geraniol,geranyl formate,herbage yield,oil content

ATTRA has funding crunch and asks our help

We received a snail-mail letter from ATTRA/NCAT (the National Sustainable Agriculture Information Service/National Center for Appropriate Technology) asking for our help because delays in getting the Federal budget through Congress are impacting their budget. You can go to their website here or through the link on the blog's Agriculture and Horticulture link list to find out more information and to donate to them if you decide they are worth it. To do so, click on the button that says "Help the ATTRA Project" near the top of the page.

Any donations are tax deductible and will be directed to their ATTRA project work, which provides assistance to thousands of people interested in learning more about sustainable agriculture practices. Some of that information is about aromatic plants.