Vetiver System and Bananas - A Senegalese, Moroccan and Californian Perspective

I thought that I would post this rather interesting exchange between Criss Juliard and Doug Richardson


Hello Doug,


Vetiver is used to surround banana plantations along the coast in Morocco as a wind break; in Senegal, we worked on an erosion protection trial in a banana plantation by planting ½ ha of banana’s with vetiver hedgerows following the contour and next to it, ½ ha without; both were on a slight 3º slope. Surprisingly, we found the banana trees produced ripe bunches about 4-6 weeks earlier in the vetiver plot than the no-vetiver plot. We concluded non-scientifically the vetiver hedgerows allowed for great moisture retention and a steadier availability of moisture to the plant; strategic conditions for better growth and yield. Neither plots had drip irrigation, which is a factor to be reckoned, but both received the same amount of gravity-fed watering.


In another experience in Senegal (it was non-scientific because it was by chance), a plant pathologist friend transferred vetiver plants I had given him near some his banana trees. He was surprised to see the banana trees’ growth and development near the vetiver superior to those further away from vetiver (even though he did not water the vetiver). He dug a small trench around one of the banana trees to look at the banana roots and found its root system decidedly turned towards the vetiver, concluding a symbiotic relation developed between the two plants, and that perhaps vetiver roots were better at dosing water than his banana watering regime.


One of the biggest problems we had early on with banana growers in Senegal was there preference to flood irrigation over drip. Slowly, large and small plantations converted to drip (measured and timed) and Senegal now exports bananas while they were net importers; part of that shift was due to the persistent civil disruptions in neighboring Ivory Coast that could no longer supply the Senegalese banana market.


I hope your expanded banana plantation is highly successful. Try placing vetiver on some parts and not in others. We have been planting bananas here in Morocco adopting a technique we found in Lebanon; a square meter hole, and a banana plant at each corner with one irrigation outlet at each hole. Planting the banana plant 50 cm below surface level eliminated nematode problems, and with one simple tie around the four grown trees we eliminate individual “tutors” and the risk anything touching the bananas.


All the best,
Criss Juliard


Dear Criss , Thanks so much for,your information about Vetiver and bananas . I delayed responding to you in the hope i would be able to obtain some photo images of a banana/vetiver planting I did here in California in 1999 . I will get them and send them to you , but for now I will say that bananas and vetiver do work very well together here also . However , vetiver's beneficial influence was not limited to bananas alone . Along with the bananas I planted dozens of other subtropical fruit trees which are considered as marginal specialty crops in our area . Almost without exception their growth exceeded our expectations. I agree with you that vetiver greatly improves the moisture regime for the plants in it's vicinity but i suspect that an equally powerful factor is the microbiological activity in the rhizosphere of the vetiver and it's attendant impact on the nutritional status and vigor of nearby plants . Vetiver's potential as a nurse crop has been touted in the literature and my experience supports that perspective . The windbreak aspect that you mentioned is also a strong contributing factor to strong rapid development of plants growing with Vetiver . Here in California I have tried both drip irrigation and microjets with bananas . Both produced acceptable results . Some of the literature suggests that drip is preferable to sprays in the subtropics because it doesn't wet and cool the bananas pseudostems in our heat deficient environment . However , the sprays provide more humidity . I need more time with a new planting to discern . I look forward to discussing this more with you . Thanks , Doug