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Desert plant maintenance

Although the January weather in Minnesota this year has been remarkably warm - well above freezing everyday for the past few weeks - still, it felt like a gift to spend 3 hours working with plants in the Conservatory's Diverse Desert room where the temperature was around 75 degrees F. Today, the task given to me was pruning and cleaning up a few of the plants in the Diverse Deserts display room. This room is open to the public. A similar climate controlled room exists on the Collection side of the Conservatory, is also open to the public but only by appointment. In the Desert Display room, the plants are in beds as they would be seen in the desert...on the ground. In the Collection room, the plants are all in pots.

A small sidewalk path curves through the stony beds of the Desert Display room. Some of the plants have become overgrown, partly obstructing the concrete pathway. The goal of the morning's work was to clear the pathway without damaging of the plants.

Desert begonia (Begonia grisea, Brazil)


Desert begonia (Begonia grisea, Brazil)

The largest of plants to be controlled was the succulent Begonia grisea. This plant is currently in full bloom at the Conservatory. It is a native of Brazil, and grows in exposed, desert-like stony outcrops. Its 5-inch leaves are plate-like and bear fine furry hairs which protect them from the full sun. 

I gathered groups of the drooping tall blossoms and tied them to bamboo stakes inserted into the bed. This allows us to enjoy the blooms without cutting them off, but yet keep them up off the walking path.

Punica protopunica (species of pomegranate tree)

Punica protopunica is a variety of pomegranate adapted to subtropical and tropical dry forests. It is native of Yemen. The plant grows as a small tree, it produces small pomegranate-like fruits which are attractive to some animals (goats). This species is not the same as the delicious P. granatum native to Afghanistan and Iran.

With long weeping branches the small pomegranate tree had to somehow be kept off the walkway. Some time ago, the central leader of the tree had been removed leaving two side-branches. They diverged from each other creating a vee-shaped small bush. Using a 4-inch metal s-hook I pulled together the two main branches to form a tall central pair. This lifted the weeping branches up away from the concrete, allowing visitors to walk past this plant without brushing against it too much.

Trichodesma scottii

Trichodesma scottii is one of several species of small desert adapted shrubs from the very dry regions of the Middle East and Africa. They require very little water despite their succulent looking leaves and mop-like flowers. This particular plant in the Display room had grown to cover most of the walkway, and it overshadowed three of the nearby plants. Using alcohol-sterilized shears I cut away about one-third of the plant. This left several large blossoms in place to be enjoyed.


Trichodesma scottii


Pereskia bahiensis bush

Rhodocactus bahiensis (formerly Pereskia bahiensis) is a tree-like cactus that is endemic to Brazil. Unlike most cacti, it has persistent leaves as well as sharp 3-inch needles. In evolutionary terms the plant sits where leafless cacti diverged from their ancestors bearing leaves only.

The plant in the Conservatory's collection has an infestation of scale insects. The insects suck sap and weaken the leaves. They are especially prevalent on the leaves at the end of the branches, where the plant's growth is the most active and nutrients most plentiful. Using a small toothbrush and 30% isopropyl alcohol I carefully brushed the scale insects off the leaves. I didn't want to spray the entire plant with alcohol because I notices there were a couple beneficial Cryptolaemus lady-beetles feasting on the scale insects. The beneficial beetles help keep the scale pests in control.



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