Pot marigold
The seed oil from Calendula contains around 60% calendic acid, which could be used in paint manufacture, varnishes, cosmetics and some nylon products.
Calendula is sown in spring, from early to mid-April, and it is important that the seeds are sown into a fine, firm seedbed with adequate moisture, to ensure an even establishment. The plants are less susceptible to frost than sugar beet or linseed, however, it is advisable to grow the crop on light, easily warmed soils.
Experiments looking into nitrogen fertilizer applications to Calendula have identified optimum nitrogen requirement for the crop at 100kg N/ha, similar to other spring-sown oilseed crops in the UK, such as oilseed rape. Applications above this level served to increase plant biomass only and could result in lodging, reducing yield.