Monday, November 29, 2010

Dragonfruit

As I mentioned in my previous post, I have been a big fan of epiphytes for a long time. In my research, I found that there is an entire family of epiphytic cactuses native to the tropics of Central and South America. Naturally, I had to find one and add it to my growing collection of epiphytes. In particular there is one species that produces a large pink fruit with green scales called dragonfruit, or pitaya. Thus began a many-year search for either a plant to grow or a fruit to try. A few months ago, my wait paid off and I found a fruit at my local grocery store. It was a bit past its prime, but it was still quite tasty. The flavor was mild and sweet. I thought the closest flavor was pear. The texture was much more like kiwi, though, with firm flesh and crunchy seeds throughout.

The best part of finding a fresh fruit was that I was able to harvest over a hundred seeds from a quarter of the fruit. I promptly planted my first set of seeds in pots and they had a really good germination rate. I am not looking forward to thinning these precious darlings.

The more I think about it, the more it makes sense that cactus would count some epiphytes among its number. After all, if you put a dry-adapted plant in a wet environment, it probably would try to colonize the sunniest, driest environment available, which is what you get out on a tree branch.  As with many epiphytes, it starts its growth cycle in the ground and then grows up the tree, producing aerial roots that help it cling to the bark. While many epiphytes eventually lose their connection with the ground, I am not sure if dragonfruits do. In cultivation, they are kept in soil, which helps get them the nutrients they need to produce fruit. For directions on growing these plants, I recommend looking up the Texas Triffid Ranch’s dragonfruit care sheet.

As for my precious seedlings, I need two to produce fruit, and they won’t begin to do so until the weight of the plant is greater than ten pounds. So I will probably keep them in a pot and trim them to keep them small until I can get my greenhouse built and enclosed. Then the plan is to plant them at the base of a Meyer lemon tree or, if I can get one, a citrus fruit salad tree*. Then the dragonfruit can grow up the tree and I can get lots of interesting fruit from one cool clump of vegetation.

*A fruit salad tree is a tree that has branches from different kinds of trees from the same family grafted on. So you can do a peach tree that also has plums, pluots, almonds, and nectarines. You can also do one with many kinds of apples and pears. I am hoping for a citrus fruit salad tree, though, with branches containing Meyer lemon, kumquat, Key lime, blood orange, and pink grapefruit.

Picture of dragonfruit fruit courtesy of Brenden Gebhart.

Thursday, November 4, 2010

Epiphytes

When I first started growing plants as a teenager, I quickly grew tired of the plain, old, boring plants that everyone else grew. I have never had a spider plant and never plan to grow one. As I learned more about different types of plants, certain types quickly rose to the top of my favorites list. The first was carnivorous plants. Succulents then became a favorite. But really, one of my longest running loves is with epiphytes.

“Epiphyte” is another word for “air plant.” They are a class of plants that grow up in trees, often with little to no contact to the soil below the tree. They are also not parasitic to the tree they live on, getting their nutrients from the air itself or what little else they can find on the branch, such as bird droppings. Epiphytes are common to tropical environments and somewhat less so in subtropical environments. While some kinds of epiphytes, such as tillandsias (which are a subgroup of bromeliads), are capable of surviving with literally no soil, most require a little. In the wild, plants firmly anchored to tree limbs attract debris and droppings, which break down into a sort of soil that collects on tree limbs. In fact, some of this soil has been found to be fertile enough that the trees grow roots out of their limbs to take advantage of the nutrients. However, the “soil” is always thin and light and drains well.

In cultivation, most epiphytes are grown wired or glued to a log or piece of bark with a little sphagnum moss packed around their roots. Some are grown in pots, but the soil is often loose and well-draining. Orchid bark is a good example of soil that is specifically designed for epiphytes, as most orchids are epiphytes. As for watering, a light mist two to four times a week will do for most species and nearly all prefer to dry out between waterings. Despite growing in wet climates, their soil is so thin that they are more adapted to dry conditions than many of their neighbors. Also many do not require any fertilizer at all. Many also prefer dappled light since they tend to have a canopy over their heads in the wild. All of these things make many epiphytes great houseplants and there are many varieties available. Below are some of the different types of epiphytes out there.

Orchids

Most orchids (with the notable exception of Paphiopedilums) are epiphytes. I had a Phalaenopsis and an Encyclia that I grew epiphytically on a log in a dry climate for over a year. While both survived, neither flowered, probably due to the fact that I rarely fertilized them and watered them all too infrequently. Some orchids do better than others in that sort of situation, but most will die if planted in soil. Plus, the amazing blooms of these plants make them worth a try.

Bromeliads

Bromeliads are probably the most famous of the air plants. While there are terrestrial bromeliads (pineapple is one), many are very epiphytic. I have three different Tillandsias that have been living without so much as a little sphagnum moss around their roots for over 4 years now. I suspect that if I was in a humid climate, I probably wouldn’t even have to spray them. If you look a little deeper than your local grocery store, you can find some bromeliads with really fascinating foliage. With proper care, they flower every 2 years or so, producing blooms that rival orchids. As a bonus, when the blooms fade, the parent plant produces pups, which are miniature plants. When those get to about half the size of the parent plant, they can be removed and planted elsewhere.

Cactus

There are actually several varieties of vining, epiphytic cacti. Their adaptation to dry climates must have made this a natural move. I can only imagine that a dry-adapted plant moving into a moist environment would cause them to evolve to take advantage of the driest microclimate available. I am just starting to grow my first epiphytic cactus, but they are still just seedlings. I’ll talk more about that in my next post.

Nepenthes

Nepenthes are commonly called “tropical pitcher plants.” They are a family of plants that start on the forest floor and then climb up the nearest tree. As with many tropical plants, they have a drip tip on the end of their leaves. Only in Nepenthes, the dip tip has become highly evolved. As the plant gets bigger and feels the lack of nutrients in its chosen home, the drip tip enlarges into a little pitcher that is used to capture and digest prey, thereby giving the plant the nutrients that growing on a tree lacks. The pitchers of nepenthes tend to be more elaborate than terrestrial pitcher plants and quite beautiful. In fact, some of the largest pitchers in the world belong to Nepenthes. Nepenthes rajah is reported to have pitchers big enough to capture a rat.

Ferns

There are a couple of kinds of epiphytic ferns. The white rabbit foot fern has white, fuzzy aerial roots that sort of look like rabbits’ feet. However, by far the most fascinating of the epiphytic ferns are the staghorn ferns. A staghorn fern starts on the side of a tree and grows two kinds of fronds. The basal fronds grow short and round and cover the root ball, protecting and enlarging it over time. The fertile fronds are what the plant is named for. They grow long and wide and sort of resemble the antlers of a moose. Mature staghorn ferns can be several feet across and are absolutely majestic plants. Thus far my attempts to grow any epiphytic ferns have been unsuccessful as they don’t tolerate the lack of humidity in my climate.

Ant Plants

While I have never grown an ant plant, and probably never will, I still find them fascinating. In addition to the usual complement of leaves, ant plants grow an enlarged, bulbous base that is riddled with tunnels. In the wild, ants move in and inhabit the tunnels, allowing the plant to take advantage of their waste.

If you are interested in possibly growing any of these epiphytes, I strongly recommend giving Black Jungle Terrarium Supply a visit. They specialize in supplies for making terrariums for poison dart frogs and have an amazing variety of epiphytic plants.

Monday, November 1, 2010

Wood Pellet Fuel

A wood pellet stove is a kind of heater that burns small amounts of wood pellets at a time with excellent air flow to produce a lot of heat without nearly as much smoke and pollution as a wood burning fireplace. It is also one of the cheaper ways to heat your home in the winter. Every winter, I stock up on several bags of wood pellet fuel, even though I don’t own a wood pellet stove. I also hold on to it until summer. So, what do I do with it, you ask?

Well, first of all, it is worth noting that I am always careful to buy the bags that say 100% organic, which means that they are composed completely of sawdust. Wood pellet fuel is made of sawdust that is dried and pressed into little pellets. When you add water to them, they swell and fall apart into sawdust. It is also worth noting that a 40 pound bag of wood pellet fuel costs about $4.

Where else are you going to get such a wonderful garden supplement for so cheap? I use wood pellet fuel as a mulch, I mix it in to soil to build organic content, and I use it as a compost amendment. For mulch, you scatter a little on the ground and then water. Be careful about how much you put down. A solid layer one pellet thick will give you about 2 inches of mulch once it has been watered, so they do swell up quite a lot. I have smothered many seedlings because I mulched too heavily with wood pellet fuel. For mixing into soil, add a few handfuls here and there to the soil as you are working it. It will add to the organic content of the soil and give the organisms in the soil something to feed off of. Again, too much is bad as large concentrations of sawdust will rob nitrogen from your soil, which isn’t good for your plants. For a compost amendment, you just throw a couple of good handfuls in the compost as needed, usually when the compost starts getting smelly. I added a small bucket of wood pellet fuel to my tumble composter this summer and almost immediately, it started to heat up, finally achieving the mix it needed to really cook. Three weeks later, it cooled off and a week after that, the compost was done and ready to use.

Consider checking out your local supply of wood pellet fuel and maybe you can put some of that precious carbon in your soil instead of putting it in the air.

Oh, and it is worth mentioning that wood pellet fuel doesn't work very well as a medium for growing mushrooms. Most mushrooms are pretty specific about whether they prefer to grow on hardwoods or softwoods. I have yet to find any wood pellet fuel that tells you what its composition is. This means that it could be 100% hardwood, 100% softwood, or, more likely, some combination of the two.