Tillandsia caerulea

The so-called “air plants” of the genus Tillandsia are true survivors. Most of them are epiphytes, meaning they grow as non-parasitic plants on trees and bushes. Less commonly, they are lithophytes, growing directly on rocks. Their roots only serve to anchor them to the substrate, and some species don't even form roots. Tillandsia grow normally even without roots and do not necessarily need to be attached to a substrate to survive. They can be grown hanging freely or mounted.

The leaves of Tillandsias are usually covered with modified hairs, known as trichomes. They are visible as a more or less dense, white fuzz on the leaves. They act like tiny sponges and become transparent when filled with water. These hairs keep the Tillandsia moist longer and give it more time to absorb water and nutrients before it dries out again. Tillandsia are among the few plants that can absorb water and nutrients through their leaves.

Tillandsia can be broadly divided into two categories, which differ in their care requirements:

• Tillandsia from dry regions usually have denser trichomes and are gray to white when dry. Their leaves are often narrow, and the entire plant is compact and firm.
• Tillandsia from humid habitats have few to no trichomes and are green when dry. Their leaves are often long and broad, and the plant has a less compact structure.

As houseplants, Tillandsia from dry regions are particularly suitable. They can and should be dry most of the time and require plenty of light. Tillandsia from humid habitats are better suited for care in a terrarium or plant display case.

This species originates from an arid region. It is accustomed to strong sunlight, little water, and high temperatures. A spot on a south-facing or west-facing window in direct sun is ideal. In summer, it can also be grown very well outdoors, preferably in light shade.

When cultivated under grow lights, it requires strong illumination. At 5,000 to 20,000 lux or 100 to 500 PPFD (µmol/m²/s), it grows well and its leaves develop ideal coloration.

It prefers humidity of 60% or less. It can also be cultivated at higher humidity, but then care should be taken to ensure that the plant can always dry out before receiving water again.

It likes warmth. Temperatures of 25 to 30°C lead to the best growth. When completely dry, however, it can also surprisingly withstand cool temperatures of 5 to 10°C without harm, although it will no longer grow at these temperatures and moisture can lead to rot.

This plant does not require a pot or substrate. It can be cultivated free-hanging or mounted. It can be attached to a cork branch, root, stone, or similar with plant adhesive or string.

Please also mount it without sphagnum moss, so that the base of the plant can dry out more easily.

Tillandsias are sprayed or soaked to provide them with water and fertilizer. They absorb water and nutrients directly through their leaves. A small hand sprayer is sufficient to care for a small collection of Tillandsias. For larger collections, purchasing a pump sprayer is advisable.

Tillandsias prefer soft water and should therefore be sprayed with distilled water, rainwater, or water from an osmosis system. If sprayed with (hard) tap water, regular rinsing with soft water approximately every 4 weeks helps prevent lime accumulation on the leaves.

This Tillandsia should always dry completely before being sprayed again. How often it needs to be sprayed depends on the temperature and sunlight. In summer and above 25°C, it can be sprayed daily; in winter and with little light, once a week is sufficient.

Tillandsias are undemanding plants that don't need too much fertilizer. As houseplants, they can be fertilized during the growing season from approximately April to October with an orchid fertilizer about every 2 weeks. For this, it might be worthwhile to purchase a second hand or pump sprayer to avoid constantly changing the water. We recommend halving the manufacturer's recommended dosage. This corresponds to a fertilizer conductivity of approximately 250 µS/cm. The conductivity can be determined with a TDS meter.

During the autumn and winter months, fertilization should be reduced, as the plants do not get enough light to utilize the nutrients. A very weak fertilization of about 100 µS/cm monthly is sufficient here.

When cared for under grow lights, they can be fertilized year-round with approximately 250 µS/cm every 2 weeks.

If cared for outdoors in summer, additional fertilization is usually not necessary; the Tillandsia obtains nutrients from rainwater and dust, as it would in nature.