Preparations made from flowers of the English or Pot Marigold (Calendula officinalis), a well-known garden plant, are widely recommended and used by western medical herbalists for minor cuts, grazes, and slow healing wounds, where an antiseptic and healing action is required. The European Medicines Agency has also approved Calendula as a traditional medicinal product for the treatment of minor skin inflammation, and as an aid in the healing of minor wounds.
However, apart from two clinical trials showing benefits from a Calendula ointment to treat dermatitis secondary to radiotherapy treatment in cancer patients (1, 2), few human clinical trials have been published.
Brazilian researchers recently conducted a clinical trial to evaluate the effectiveness of Calendula extract in the treatment of non-healing venous leg ulcers (3). Treatment consisted of a twice daily spray application of a hydro glycolic extract of Calendula, or the standard hospital procedure which included the use of collagenase, the antibiotic chloramphenicol, and 1% silver sulfadiazine cream. Both treatments were given for a period of 30 weeks or until ulcers healed, and nursing staff examined and assessed patients every two weeks, during which the wound area was measured and clinically evaluated.
Swabs were collected from the wounds before starting treatment, and these showed Staphylococcus aureus to be the predominant microorganism in both the control and Calendula groups, with Pseudomonas spp., Klebsiella spp., and Escherichia coli being found in the wounds of some patients. The size and duration of ulcers prior to treatment was similar in both groups, and patients had an average age of 68 years in the control group of 19 patients, and 63 in the Calendula treated group of 38 patients.
After 12 weeks treatment, 39% of Calendula-treated wounds were completely closed, but none in the standard treatment control group. After 30 weeks treatment, 72% achieved complete wound closure, while only 32% were closed in the control group. An average of 12 weeks was needed for healing to occur in the Calendula-treated group, but 25 weeks in the control group. No adverse events were observed during the Calendula treatment.
Favourable outcomes were also achieved in a Serbian clinical trial which involved 21 venous ulcer patients who applied Calendula ointment twice daily for 3 weeks (4). Calendula treatment reduced the total surface of the ulcers by an average of 41.7%, but only by 14.5% in the control group of 13 patients treated with saline dressings. Complete wound closure was achieved in four patients treated with Calendula.
These two studies show a significant acceleration of chronic venous ulcer wound healing through twice daily application of topical products made using Calendula flowers. While a 3 week treatment period was beneficial, continuing this for longer periods is recommended to achieve optimal results.
Beneficial effects of Calendula cream for the treatment of vaginal Candidiasis (thrush), were also reported from a recent Iranian study involving 150 women aged 18-45 years(5). Participants used a 5-g vaginal applicator of Calendula or clotrimazole (an antifungal drug) cream for seven nights before going to bed, then were assessed at two post treatment time points.
Compared to the clotrimazole group, fewer women in the Calendula group tested negative for Candidiasis at 10–15 days following treatment (49% vs 74%), although both treatments had similar effects at improving clinical signs and symptoms and sexual function. At a 30-35 day post treatment follow up, however, signs and symptoms were less severe in the Calendula treated group, and women treated with Calendula were significantly less likely to have suffered a recurrence of Candidiasis, than those treated with clotrimazole.
These results suggest that a seven day course of intravaginal calendula cream is safe and can be effective for the treatment of vaginal Candidiasis, but seems to have a delayed effect compared to clotrimazole. However, Calendula use may have better long term outcomes such as a lower risk of recurring infections, even after a 7 day course.
While a longer duration of Calendula use may have greater effectiveness in the treatment of vaginal Candidiasis, particularly as resistance is increasing to clotrimazole and other antifungal drugs, this trial provides encouraging data to support its use for this annoying problem experienced by a large number of women.
Clearly the impressive healing capabilities held by the attractive and bee-loving flowers of this easy to grow plant, extend beyond minor cuts and grazes, to include more chronic and debilitating conditions such as venous ulcers and vaginal thrush.
Refs:
- Pommier P et al, J Clin Oncol 2004; 22(8):1447-1453.
- Schneider F et al, Rev Esc Enferm USP 2015; 49(2):221-228
- Buzzi M et al, J Wound Care 2016; 25(12):732-739
- Duran V et al, Int J Tissue React 2005
- Saffari E et al, Women & Health 2016; Nov 23:1-16




While not pleasing to all, other flowering plants such as the invasive introduced gorse (Ulex europaeus), presently plays an important role as a food source for bees in some areas. However, we should be planting other native species such as Hoheria (Hoheria populnea), Whauwhaupaku or Five Finger (Pseudopanax arboreus) and many others, to provide pollen and nectar as a replacement for that from this imported thorny plant.

The New Zealand native Mānuka (Leptospermum scoparium) is one of these, and the ability of certain forms of Mānuka Honey to act as potent healing agents for wounds and ulcers, is becoming increasingly recognised(8). Many clinical trials have now shown manuka honey dressings to have unique healing properties in chronic leg ulcers and other stubborn skin infections, and synergistic antimicrobial activities with various antibiotics, have recently been reported(10,11).
he haze contains particulate matter, fine particulate matter, heavy metals and poly aromatic hydrocarbons, and at its peak can measure hundreds of kilometres across. As well as affecting Singapore’s air quality and visibility, the air pollution can spread to Malaysia, southern Thailand and the Philippines. This can have a major impact on the health of the people and plants of these countries, and of course those of Indonesia itself.
While considering this situation, I couldn’t help notice the presence of palm oil still in chocolate sold throughout Singapore, unlike certain other countries where it has been removed due to public concerns around the environmental impacts of a huge increase in palm oil plantations. Similarly the importation of palm kernels for use as a supplementary feed to dairy cows in New Zealand, needs a mention. Reflecting on this as well as the widespread use of palm oil in cheap vegetable oils and in many other food and non food consumer items found globally, there is clearly a need to address the underlying cause of such environmental pollution and factors responsible for poor human health, in a more integrative way. This burning of indigenous forests in Indonesia is related also to poverty as well as poor regulation by authorities there, but corporate greed, consumer usage and lack of awareness or concern for environmental and economic impacts, is contributory.
Ashwagandha (Withania somnifera) is a herb native to India and the Asian subcontinent, used as a tonic and treatment for a wide range of health conditions and perceived benefits. Known among herbalists as an ‘adaptogen’, its best known action is to help improve the body’s resilience to stress. Withania normalises blood levels of cortisol and other adrenal hormones during chronic stress, and exhibits a large number of actions suggesting an ability to insulate against adverse environmental stressors. This results in reduced anxiety, and a subtle but welcome retention of a sense of still being ‘in control’, during times of stress (2,3).
Science is also starting to suggest superior nutritional properties for organic crops. A ten year comparison of the influence of organic and conventional crop management practices on tomato flavonoid content, measured higher levels of the antioxidant lavonoids quercetin and kaempferol in organic tomatoes(2). Studies have also found enhanced organoleptic and taste qualities of organic versus non organic apples(3).

Most medicinal herbs are grown in developing countries, where programmes to control exposures to agrichemicals are either limited or non-existent. Many agrichemicals are toxic to handle, and pose significant risks, particularly in the event of accidental spills or inhalations. Children are particularly vulnerable to their harmful effects, with even very low levels of exposure during development potentially having adverse health effects. The World Health Organisation estimates that there are 3 million cases of pesticide poisoning each year and up to 220,000 deaths, primarily in developing countries.


