In recent years Tillandsia, commonly referred to as air plants, have become increasingly popular. These little epiphytes fly in the face of our understanding of traditional plant requirements, and that uniqueness makes them intriguing. Because of their mysterious nature, creating beautiful air plant displays is so effortless that anyone can do it — one of the reasons they make such great gifts. Unfortunately, if they are not grown in the right conditions, they can also be relatively easy to kill. In this article, we will cover Tillandsia growth patterns, general care information, how to build a Tillandsia terrarium, and the equipment necessary for them to flourish.
As with all air plants, we need to understand how Tillandsia grow in order to best care for them. Tillandsia are epiphytes, which means that they typically live on other plants in a non-parasitic manner. They can be broken into two distinct categories: mesic and xeric. Mesic varieties are often found high in the tree canopy of the American tropics, which informs us that they typically like bright indirect light, good airflow, frequent rainfall, and have roots meant for anchoring. On the other hand, xeric varieties grow on exposed cliff faces and rocky outcroppings. These types of air plants need far less water, prefer small doses of direct sunlight and plenty of air movement, and also have roots meant for anchoring. The xeric varieties differ from the mesic in the trichomes that cover their leaves to draw extra moisture from the air. They almost appear to have a silver fur, as opposed to the shinier greenish hue of the mesic air plants.
Understanding the native conditions under which Tillandsia thrive allow us to create a better environment for them in our homes. Since all Tillandsia do well under humid conditions, I always recommend keeping them in an open terrarium. The trick is to create an environment that has a higher relative humidity than our typical homes, but also has good airflow. Keeping a Tillandsia under a cloche or in a closed terrarium can only end with a doomed plant. So look for glass containers with holes in the sides, or a large top opening.
While traditional terrariums require many layers (as discussed in a previous blog post), an air plant terrarium really only needs one: the drainage layer. The goal of the drainage media is to keep the plants from ever sitting in water and can consist of almost anything that won’t rot. You can also add some moss or lichen for decoration and to increase the humidity.
Lastly, but perhaps mostly importantly, Tillandsia need proper light levels. Many people try to keep their air plants in too low light. Our homes are caves compared to their natural habitats. Ideally, try to keep them in either an east or west facing window. They can also be away from or to the side of a bright south facing window. The objective is to have bright indirect light during the middle of the day with a couple hours of direct sun either in the morning or afternoon.
So, to recap, the basics to create a good home for Tillandsia are an open glass vessel, inert drainage media, perhaps some decorative moss, and proper light levels.
The equipment to properly water and feed these little oddities are mostly items you can find around your home. In her book Air Plants: The Curious World of Tillandsias, Zenaida Sengo best describes how to water air plants by comparing them to a kitchen sponge. You don’t want the sponge to dry out completely, and you can water it by several different methods: frequent misting, regular dunking, or occasional soaking.
Misting should occur every day or every other day using a small spray bottle. To dunk a plant, you can run it under the sink in a colander, in a terrarium with a deep drainage layer, or dunk it in a bowl of water two to three times a week. To soak the plants, remove them from their container and soak them in a bowl of water for 10 minutes to an hour once a week. Regardless of the method you choose, water collected in the cup of the leaves should be shaken out to prevent the plants from rotting. Remember: xeric varieties will need to be watered less frequently.
Like all plants, Tillandsia need to be fed occasionally for optimal growth. I recommend combining a kelp product in solution with a balanced water soluble orchid food. You can feed them with half a dose every couple weeks, or a full dose every month to three months.
With this basic understanding, you should be ready to successfully cultivate these little wonders!