I was worried that it would be hard to grow Moringa peregrina here. The rainfall here is about 750 mm per year, considerably higher than in most of the places where Moringa peregrina grows. Also, I was worried about a moringa catch-22: Moringa peregrina plants can take a long time to grow aerial stems in pots, but I didn’t want to plant them out in the ground in the botanical garden until they grow aerial stems. Like many species of Moringa, Moringa peregrina has a tuberous juvenile stage. It grows, often for many years, as just a tuber underground, throwing up slender shoots every year that then die back to the tuber. Only after the tuber reaches a certain size does the plant form an aboveground stem that does not die back every year. Even in the first few years this stem can still die back all the way to the tuber if there is a very severe drought. But eventually the stem remains year after year, the beginning of the life of the plant as a tree. With a little patience, though, and relatively large pots, the M. peregrinas have started to form large enough above ground stems, 10-40 cm tall, that I feel confident about putting them out in the ground.

Other species, like Moringa concanensis or M. drouhardii grow in dense tropical dry forest. They compete well with weeds and other forest plants. Moringa peregrina often grows on bare rocky slopes where they are the only tree in the landscape. Not accustomed to competition, I wanted to make sure that the peregrinas would do well when planted out. I was also worried that the relatively high humidity here would be a problem. It doesn’t rain 8 months of the year here, but we are so close to the coast that the humidity is always high. So I was concerned that the plants might be vulnerable to fungal infection and rot. Once the plants are established and growing in pots, though, we have had no losses, and they are doing just as well as all the other species.

So, in June we made a trial planting of four M. peregrinas of various provenances on the driest, most exposed portion of the ridge that runs through the collection lot. It seems like the perfect place for the drought-loving M. peregrina. Their aboveground growth has been slow to date—the tallest plants are just 40 cm tall—and I suspect they are busy allocating resources to roots. But they are holding their own and producing aboveground growth much faster than I have ever seen in pots. So we declared the planting a success and in September started about 10X10 meters of a steep, west-facing slope for planting out more Moringa peregrina.

Because Moringa peregrina grows in the open, we wanted to plant them out on the most competition-free slope possible. The Taminco company here in Mexico very kindly donated 20 liters of metamsodium, a soil fumigant. After a good rain had soaked the soil, we diluted the metamsodium, which in this case came under the evocative trade name of Mercenario, and poured it into the soil. We watered it in and then covered the entire parcel with plastic and weighted down the plastic around the edges. After a month, we took off the plastic and let the soil air out. Metamsodium is wonderful because it kills absolutely everything—weed seeds, plants, nematodes, fungi, provided that it is sufficiently concentrated and goes deep enough. 

After a month’s airing out, we noted with a little dismay that there were some Antigonon vines coming back from their underground tubers. This is a horrible weed that roots everywhere and produces very firmly rooted tubers everywhere. The vine itself is fragile so it is impossible to pull the tubers out. A perfectly designed weed but a nightmare to control as it reaches up, sometimes overnight, to grab onto the moringas and smother them. This is almost certainly not the fault of the Mercenario but our not watering in the fumigant well enough on in all areas.

Undaunted, we whacked back the Antigonon and planted out a little over a dozen Moringa peregrina saplings to see how they do. Now, just a few days after transplanting, they look great, with no transplant shock apparent. Given that it grows in fairly readily accessible places like the Golan, Egypt, etc., someone else must grow M. peregrina in the Americas, but I don’t know of anyone. Check back and hopefully in a few years in this space I will be telling stories about the first flowering and fruiting of M. peregrina here, so far from their native habitat.