Tag Archives: houseplant

Marimo: “Houseplant” for the New Generation

one small Marimo to take home, with googly eyes attached

Usually when I see or hear of something three times in a row, it peaks my interest. Recently I had seen images of Marimo on Facebook – green, moss-like balls in water. Last week, City Planter, a local plant business, was selling them at the Philadelphia Flower Show in water-filled plastic pouches. I did not buy one but I thought it would be a great gift for my kids as they move into college dorms this fall. This week, I received an e-mail from The Sill announcing they have Marimo as a “houseplant” in stock again.

Marimo are balls made up of green algae (Aegagropila linnaei). The algae is a filamentous form where the filaments grow out from the center in many directions. The rolling nature of the water in the lakes in which they are found mold the algae into spheres. This filamentous algae is found only in a few lakes, one of which is Lake Akan in Japan. Marimo is the Japanese word for the balls.

Marimo grows slowly, just a few millimeters per year. They are long lived in their natural environments, lasting over a hundred years and reaching a foot in diameter. The Marimo balls that are sold as “houseplants” are juveniles, only a few inches in diameter.

Marimo can be kept in glass bowls by themselves or in aquariums. However, some fish such as goldfish eat the balls so check with your pet store first. The balls photosynthesize just like a houseplant and prefer indirect light or aquarium lights. If separated or torn apart, they will not die. However, you may have to hand-mold them into balls again. They cannot be allowed to dry out or they will die.

individual glass container of one Marimo to bring home

In nature, Marimo are spherical because of the lake’s rolling water but in a glass tank they may lose this shape because the water is still. Simply hand roll the Marimo to retain the shape. This also allows other sides to receive light evenly. Because they come from cold lakes, they prefer cool, clean water which means the water in the glass bowl cannot be allowed to heat up (which will happen with sun or direct light) and has to be changed every two weeks.

Theoretically, Marimo balls will outlive you if you treat them right. Not like the goldfish I got for my kids when they were in elementary school. In the fall, as my twins head for college, I will buy them glass bowls of green Marimo balls, the low-maintenance “houseplant” for the next generation.

holding tank of many Marimo for people to purchase individually

Poinsettia Pointers: Before and After the Holidays

Odds are you have a poinsettia in your home for the holidays. In the United States, poinsettias are grown in greenhouses and programmed to bloom in time for Christmas. Try to emulate the bright light and balmy 70 degrees the greenhouse has to offer in your home so your poinsettia will survive the holidays. Keep the soil moist but don’t let the roots sit in water. Make sure the pot has drainage holes. If it is in that decorative foil, either remove foil or cut bottom out of foil so excess water drains out.

After the holidays, grow it as if it were a houseplant. With luck, you may be able to see colored bracts (the “flowers”) again next year. Keep the plant in bright light and 70 degree temperature. In the spring, cut the stems back about half the length. Keep indoors or put outdoors in the warm summer months. Apply a houseplant fertilizer and make sure the plant does not dry out. In June, transfer into a slightly bigger pot. In September bring the plant back indoors. To induce flowering, give the plant bright light each day and fourteen hours of uninterrupted dark each night beginning in early October (as in cover with a box or put in a closet). Keep the soil moist but stop fertilizing. The color should form on the bracts in six to eight weeks.

Garden Bloggers Bloom Day: Shamrock Plants

Although it looks like a three-leaf clover because of its trifoliate leaf structure, a shamrock plant is actually a species of Oxalis. These green or burgundy foliage plants are often sold as novelty houseplants, especially around St. Patrick’s Day. The small flowers rise high above the leaves with five white or pink to white petals. Most people grow them as houseplants but they can be grown outdoors in the summer here in Virginia. Because they are small, it is best to grow them in containers (off the ground level) for better viewing. Shamrock plants grow from rhizomes called pips which can rot if overwatered so it is best to let the soil dry out a little between watering. Eventually the plant will go through a dormant period and produce more pips that can be dug up for more plants.

The plant is best grown in indirect light with cool temperatures. Usually it is only after you purchase the plant that you learn of its charm:  the leaves move up and down every day. In the daytime, at maximum light, the leaves are horizontal or open. By nightfall, when light levels are reduced, the leaves bend down almost as if the plant is wilting. Don’t worry, this is normal and does not mean that you have to water.

Shamrocks are beautiful houseplants but there is one caveat: they do not combine well with pets. Oxalis contains a high level of oxalic acid, which can be poisonous.

Keep that Poinsettia after the Holidays!

Odecember2015poinsettia 007dds are you have a poinsettia in your home for the holidays. In the United States, poinsettias are grown in greenhouses and programmed to bloom in time for Christmas. Try to emulate the bright light and balmy 70 degrees the greenhouse has to offer in your home so your poinsettia will survive the holidays. Keep the soil moist but don’t let the roots sit in water and make sure the pot it came in has drainage holes. After the holidays, grow it as if it were a houseplant. With luck, you may be able to see colored bracts (the “flowers”) again next year. Keep the plant in bright light and 70 degree temperature. In the spring, cut the stems back about half the length and either keep indoors or put outdoors in the warm summer months. Apply a houseplant fertilizer and make sure the plant does not dry out. In June, transfer into a slightly bigger pot and in September bring the plant back indoors. To induce flowering, give the plant bright light each day and fourteen hours of uninterrupted dark each night beginning in early October (as in cover with a box or put in a closet). Keep the soil moist but stop fertilizing. The color should form on the bracts in six to eight weeks.december2015poinsettia 010