Skip to main content

Orchid Maintenance Up in the Rafters

Many species of orchids are epiphytic, meaning the live up in the trees. The University of Minnesota Conservatory greenhouse has one remarkable example of an orchid in this sort of habitat. This particular vanda orchid has lived for many years in a 3 x 3 ft wooden basket. In 2019 the plant was moved from the old greenhouse and hoisted up into the rafters of the tropical room of the new greenhouse. It has continued to grow to weight of approximately 50 lbs. The orchid has several branches growing out from the root ball, each branch measuring up to 3 feet in length.

After so many years of growth, the root ball has begun to rot and collapse. Today's chore was to help the greenhouse staff to assemble ladders and gather equipment to remove the old orchid and replace it with cuttings from the old plant, now in a new basket.

As the staff cut apart the old orchid, large sections of the orchid fell to the floor. The cuttings were free for the taking since they were to be disposed of in the organic waste pile. But, the cuttings came with a warning: the orchid was infected with an orchid virus. Any tool used on the plant was likely to infect any other orchid plant if the tool was not properly disinfected.

Plants, much like people and animals, suffer from a variety of infectious bacteria and viruses. Orchids are a host to more than 50 different types of viruses. The two most common are cymbidium mosaic virus and odontoglossum ringspot virus. These two are major sources of plant loss for orchid growers. Once infected, the virus spreads to all parts of the orchid plant. They are specific to orchids and do not infect other plant species. The signs of infection are yellow, brown, and sunken coin lesions on leaves and blossoms. Once infected, the virus cannot be removed from the plant. Not all infected plants will show active lesions, depending on the variety and health of the orchid plant. Prevention is limited to ensuring tools are properly cleaned before and after use.

Orchid cuttings in a new basket; the strap-like leaves of the vanda orchid are just barely visible at the edge of the basket. Arching over the basket are branches of a fig tree.

After helping with the orchid, I chose another chore from a list of tasks. There are four different display rooms open to the public (another four rooms are not open to the public without supervision). Each room represents a particular climate biome. Since they are frequently seen my the public, I chose to clean plant debris and weeds from the gravel beds in two of the four public display rooms. As I worked, I attempted to answer visitor's questions about plants in the collection.

Now clean gravel bed in the Mediterranean scrubland room

I'm always on the lookout for plants new to me. I noticed this bright red bell-shaped flower of wooly kohleria (Kohleria hirsuta var. hirsuta). The plant is native to South America and the Caribbean Islands. It is used to a warm dry habitat and prefers to scramble over rocky well-drained ground. I suspect the fine hairs help gather moisture and perhaps protect from insects.

Wooly kohleria (Kohleria hirsuta var. hirsuta); native to South America and the Caribbean Islands. Note the fine hairs on the leaves and flower edges.

Labels:

Comments

Post a Comment

Popular posts from this blog

I celebrate learning this about cycad plants

I didn't know that the cardboard palm - Zamia furfuracea - is a cycad. It isn't a palm tree (don't judge me, I'm not a botanist). But it also doesn't look like the other more familiar types of cycads with their fluted upright palm-like fronds. I didn't know it is said to be the second most commonly cultivated cycad, after Cycas revoluta . I didn't know this plant is unrelated to the common ZZ plant - Zamioculcas zamifolia - although they have a similar appearance. Before today I didn't know any of these things, but now I am happy to have learned them. From the parking lot I walked to the U of M Conservatory greenhouse in near-zero F weather. Stepping into the tropical spaces was a joy of its own. But being able to learn new information and experience new procedures was a compounding factor. Joy squared. During my 3-hour volunteer shift, my initial task was to clean the parasite critters (mealybugs and scale) from the stems and leaves of the cycad, Zami...
Post a Comment
Read more

Mobile indoor green wall

Finally, after three years... my plant vines have grown and spread to be green wall that I had hoped for. I'm not sure it would have taken as long if the plants were in a more humid, sunny climate, et cetera. But given our indoor Minnesota location - even with a southwest exposure - the vines have needed that amount of time to climb the six feet from the base to the top rungs of the metal grid supporting them. The result has been worth the effort. And to be honest, I didn't have to wait three years to begin enjoying the green wall. The vines were already attractive when only half way up the trellis. A metal grid is filled with mix of Epipremnum aureum cultivar "Marble Queen", Epipremnum aureum aka golden pothos, and Philodendron Brasil . Architecture of the green wall The initial intent of the project was to grow a green wall, in an apartment, that could be moved around to be able to clean underneath, and also to provide a mobile room divider for our open-plan loft....
Post a Comment
Read more

Strung out in the greenhouse

The assignment for my four-hour volunteer shift at the University of Minnesota Conservatory greenhouse was clearly listed on a whiteboard, with my name attached. Since most of the tasks involved working with strings of overhead cables or air tubing, much of my shift was spent at the top of a ladder. Vining plants are limited to only a few of the many benches in the greenhouse. Steel cables are strung above the benches to support their growth. Because many plants grow in a small space, part of the challenge is to untangle and separate the vines so that they don't strangle each other. Not many of the vines are blooming at the moment, as it is winter. However, Thunbergia grandiflora is producing a few lovely blue flowers (its tendrils grow clockwise, hence the common name Bengal clockvine). It's a popular houseplant, but it has become an invasive weed in parts of the world, like Australia, especially around waterways. Thunbergia grandiflora; notice small brown scale insects sucki...
Post a Comment
Read more