Pigeon Pea

The pigeon pea has been grown by humans for more than 3,000 years and in some parts of the world it is an important source of protein. In the U.S. it has grown a bit out of favor among consumers and gardeners but it still has its uses, both as food as well as green manure or other cover crop uses.
Pigeon pea is scientifically known as Cajanus cajan and is, as the common name suggests, in the pea family or Fabaceae. It goes by various other names around the world, the more common English names being tropical green pea, no-eye pea, and Congo pea. In India, the split form of the pea is call toor dal and is a popular component of many recipes, most specifically lentil soup (dal).

Pigeon pea was first cultivated and is most likely native to southern India. From there it travelled to East and West Africa and from there to Europe and the Americas (via the slave trade). Now it is grown throughout the tropical regions of the world and has been incorporated into many traditional dishes.

In Hawaii, the pigeon pea has sometimes escaped from cultivation and has become sparingly naturalized. Although it survives on its own in Hawaii, it is not a particularly invasive species and tends to be found in already altered ecosystems. It has been around long enough to have a Hawaiian name (though it is not a Hawaiian native) and is known as pī nūnū or pī Pokoliko. “Pī nūnū” is a literal translation of “pigeon pea” and “pī Pokoliko” is a literal translation of “Puerto Rican pea.” 

Pigeon peas and rice is a traditional Puerto Rican dish and most likely the origin of the Hawaiian name for the plant. It is interesting to note, though, that the pigeon pea has been in Hawaii since at least 1864, 36 years before the first Puerto Ricans were brought to Hawaii to work on the sugar plantations. Who actually brought the pigeon pea to Hawaii is not documented.

According to the Manual of the Flowering Plants of Hawai`i (published in 1990 by University of Hawaii Press and Bishop Museum Press) the pigeon pea may be found “apparently naturalized in open disturbed areas such as roadsides, pastures, and cane fields” from about 80 to 2000 foot elevations. It can be found on all the main islands in Hawaii.

Pigeon peas come in a variety of forms. There are annual varieties and short-lived perennial types. In Hawaii we have the perennial types but there are probably seed companies can that can sell you the annual varieties. The perennial ones can be short shrubs averaging 3 or 4 feet tall or taller shrubs, up to about 12 feet tall, when flowering.

Pigeon peas are easy to grow from seeds, though it may take a little while for the plants to take off. The seed germinate in one or two weeks from planting and may stay only a foot or two tall with one main stem for the first month or two. Once they get themselves established, though, they start growing quickly and within three to five months they are full and bushy. I tend to trim mine to keep them under control and use the trimmings in my compost or as nitrogen-rich mulch. This may slow down the flowering process but the clippings are well worth the wait and the bushier plants end up having more flowers – and seeds.

As a legume the pigeon pea is a nitrogen fixing plant. That means they have associated bacteria that take nitrogen from the air (N2) and change its form into one that is available for plants (NH4). Most parts of the plants are fairly high in nitrogen and as they decompose, add nitrogen to the soil (or compost) making it available to other plants. Nitrogen is also left in the soil by the decomposing roots, enriching the soils for other plants. This is what makes pigeon peas one of the recommended “green manures” used to enrich soils.


Even if it isn’t used as a green manure (worked into the soil before allowing to flower) but is grown as a crop, it is good to follow a pigeon pea crop with plants that need richer soils, such as corn or squashes. The bushy types can be trimmed and the main stems left behind to allow vine crops to grow on them. Or the whole plant can be trimmed to the ground (not disturbing the soil too much to allow the roots to decompose) and grain-type crops or greens can be grown, to use the released nitrogen.

As a legume, the pigeon pea has a typical pea-like flower. Those grown in Hawaii have yellow flowers with darker veins. They are attractive to honeybees, leafcutter bees and carpenter bees, as well as other pollinators, and relatively quickly followed by green seedpods. The seedpods are 1½ to 2½ inches long and about ¼-inch wide with three to nine seeds in them. The seeds are a little less than ¼- to a little more than ⅓-inch in diameter and slightly flattened balls. The range in color from light tan to nearly black.

The seeds can be eaten green or dried. In some parts of the world the pods themselves are eaten. Boiled green, nearly-mature seeds pods can be eaten like edamame or the green seeds removed and quickly parboiled and eaten like green peas or added to soups and stews. The dried seeds can be used any way dried beans are used. Pigeon peas and rice is particularly flavor-full and provide a complete protein for those trying to reduce or eliminate meat products from their diet. Pigeon peas are an important part of a vegetarian diet in parts of India.

So even though most Western gardeners and farmers have relegated the pigeon pea to green manure or animal food status, give this old staple a try. It is easy to grow, leaves garden soil in better shape than before it was planted, and adds some flavor to many dishes.

Grow Your Own Chia

If you’re of a certain age you remember the commercials for chia pets – those terra cotta animal figurines that you spread with seeds to grow their “fur.”  Or maybe you know chia as the newest addition to a healthy diet of smoothies and salads. Chia seeds are available in small health food stores and the big warehouse chains and everyplace in between.
Chia seeds

Chia, Salvia hispanica, is a member of the mint family (Lamiaceae) and most closely related to the sages. It is an annual that grows quite quickly from its small seeds. The plants look a little bit like pineapple sage but have a narrower spread and grow a bit more upright. The leaves are opposite each other and when the plants are two to three feet tall green flower spikes start to form. Once the spikes get about 2 to 4 inches long blue or white (mostly blue) flowers start to appear. The spikes can get 4 to 8 inches long, the tallest ones usually at the center of the plant and the side shoots with smaller spikes. Once the flowers have all faded away the spikes will turn a light tan color.

The flowers are typical of plants in the mint family.
The plants are very easy to grow. The small seeds can be planted in rows or thinly scattered on a bed. If watered in right away, there is no need to cover them in soil. you can run a rake over the would to mix in he seeds, but a good watering will do the same. If planted in rows the rows should be 2½ to 3 feet apart. Once the seedlings have germinated and are 1 to 2 inches tall they should be thinned to a final spacing of 1½ to 2 feet apart. If scattered in a bed, the plants should be thinned to have about 1½ to 2 feet between each plant.


A chia plant just starting to flower.
Most of the flower spikes will mature at the same time. Once the majority of the spikes have dried to a light tan color, the whole plant can be harvested. You can extend the harvest seasons by a few weeks by just taking the mature spikes leaving the younger ones to mature later, but the extra seed production is not really worth the extra effort.

So go ahead and harvest the whole pant near the base and hang the plants upside down in a well-ventilated, dry area to mature a little more, maybe a week or two. Cut the spikes and place them in a container. Using gloves, strip off the fruit, making sure everything but the stems falls into the container. At this stage you can use your hands to break everything up. Alternatively, you can use one of those hand blenders to break it all up (don't worry, the seeds are so small the blender won't break them).

A chis plant in full bloom.
Tap the container on the sides to make the seeds fall to the bottom and the chaff rise to the top. Tip off as much chaff as possible and repeat until most of the chaff is gone. At this stage it can get a little hard to get the remaining chaff separated from the seeds. I use a fan at medium speed to do the final separation. I put the seeds in a shallow container (with about 2- to 3-inch sides) and tilt it slightly toward the fan, maybe 2 to 3 feet away from the fan. Toss the seeds an inch or two into the air and the fan should blow away most of the chaff. Some seeds will also blow away but most will fall back into the container.

Once the whole spike turns a light tan
they should be harvested
Repeat the above process a few times until all that remains are the seeds. Chances are, there will still be a little bit of chaff but these will rise to the top of the seeds if they are shaken. The remaining chaff can be picked out by hand.

Some chia may grow again in the same spy as before from seeds dropped by the plant. You can let these grow into the next crop but eventually you will need to replant to produce a reliable crop. There seems to be little chance chia will become a weed in your garden, but do be aware they they may come up from time to time a little while after harvesting.

Set aside some of the seeds for your next crop and use the rest however you like. Chia seeds are similar in nutrient content to other edible seeds such as flax or sesame. Current health claims are not extensively researched and though some preliminary results are promising, don't believe everything you read.

The seeds can be added to other foods as a topping or put into smoothies, breakfast cereals, energy bars, yogurt, or consumed raw. When soaked in water or other liquids, chia seeds absorb up to 12 times their weight of the liquid. They develop a gel-like coating that gives chia-based beverages a distinctive texture. The can also be milled and eaten that way or cooked into breads and other baked goods.
Store your harvested and cleaned seeds in an airtight container.

Cannibal Snail – An Introduced Friend, or Terror?

It sounds like a good idea for those of us who have spent hours fighting slugs – a snail that doesn’t eat plants but spends its time looking for and eating other snails and slugs. "A predator of snails and slugs?" you say. Sign me up!

A rosy wolf snail, note the typical light-pink, elongated
shell
That’s exactly what happened in in 1955. Some eager snail-hater, well, someone who was fed up with the giant African land snail (Achatina fulica) that was eating its way though agricultural fields in Hawaii, decided to bring the rosy wolf snail (Euglandina rosea) to Hawaii. (Of course, some other “wise” soul brought in the giant African snail – but that’s another story.) Bring in a snail–eating snail to eat up the pest snails, and slugs, while they are at it.

But they didn’t look at the big picture. Hawaii, and other Pacific Islands where the rosy wolf snail has been introduced for snail and slug control, is also home to some very special native snails.

Native Tree Snails

These native snails evolved here in Hawaii and are found nowhere else in the world. And until humans showed up, had very few, if any predators. Oh, maybe a bird or two ate them once in a while, but certainly none of their own kind. And these native snails don’t even eat plants. They eat algae that grows on the leaves of trees. They keep the tree leaves clean, causing no harm and helping out in their own way.

A giant African land snail, the original target for the
rosy wolf snail.
Along come humans. The first humans brought rats. Rats love to eat a lot of things, and particularly like snails. They started eating the Hawaiian tree snails. Then along come European humans, and they bring a whole host of other predators, including themselves. It was a popular hobby to go into the Hawaiian forests and collect the beautiful “forest jewels” and put them on display. And, as mentioned above, someone bright fellow thought they’d bring in the giant African land snail as a food item. Escargot, you know. That bright idea went bad and the giant African snail started eating human crops all over the place. Yikes! What to do?

A native Hawaiian tree snail on Oahu,
Achatinella mustelina, listed as endangered
by the federal government, largely due to the
presence of rosy wolf snails.
Bring in a carnivorous snail, one to eat the African land snail. So in 1955 they introduced the rosy wolf snail, Euglandina rosea, also known as the cannibal snail. One snail to eat another snail. But the giant African land snail is, large, as it clearly says in its name. And the rosy wolf snail is quite a bit smaller. Not that the rosy wolf snail won’t eat giant African land snails if it gets a chance, it just prefers snails smaller than itself. When it comes across small snails, it will eat them – all of them – from soft body to shell. It loves to eat our endemic snails.

There are places in Hawaii where expensive snail-proof fences have been put up to protect our native tree snails. To have to do something like that to protect our native animals is pretty sad, and unless we come up with a way to eradicate the rosy wolf snail from native forests, an expensive method that will create in-place zoos for something that was here long before any humans arrived.

Rosy Wolf Snails

Rosy wolf snails are native to the Americas, and in North America is native the southeast US. From there it has been introduced to many parts of the world for snail control, and almost always has caused ecological damage by eating native snails.

What a rosy wolf snail should look like after being seen
in a native forest,
The rosy wolf snail eats snails and slugs, but it is a generalist. They eat other snails, slugs of all kinds and even each other. More mature rosy wolf snails will gobble up smaller members of their own species, hence, the name "cannibal snail." They show a preference for smaller specimens but if they can overpower larger ones, they maneuver the snail so they can get to the soft, fleshy parts.

According to the Global Invasive Species Database, the rosy wolf snail is considered one of the world's 100 worst invaders.  Its presence of has been strongly linked to the extinction and decline of numerous snail species in every area where it has been introduced.

Once introduced they are not too particular as to habitat. They live just as happily in urban, disturbed habitats as they do in native, lesser or undisturbed habitats. Maybe they are good for gardeners, but they are devastating to our native snail fauna. And there is no evidence that has shown that when they have been introduced they have ever controlled populations of giant African snails.

Mating rosy wolf snails.
I won’t say that if you see one you should kill it without a thought. In your garden, it might be doing some good, keeping the other terrestrial mollusks under some control. But if you are hiking, or you see this snail anyplace other than your or someone’s garden (that is nowhere near a native forest), step on it and do the native snails a favor.
A rosy wolf snail chowing down on a slug in the garden.

A rosy wolf snail decides to take on a giant African land snail.

First, an attack to the big guy's neck.

Next, an rear attack.

The smaller rosy wolf snail finally gave up and the two snails went their separate ways. The giant African land snail was later crushed by a human foot. The wolf snail was allowed to take on slugs and smaller garden snails in this urban garden.