Sharp Spray of Water

Nearing the end of August, we're on the downhill slope of summer in Minnesota. Today is the beginning of the great Minnesota get together - the Minnesota State Fair. I am not a frequent or enthusiastic fair-goer. Large crowds and long lines make me feel anxious. I mention it only because the fairgrounds are adjacent to the University of Minnesota St. Paul Campus, where I volunteer.

Today on my bicycle ride to the greenhouse I passed hundreds of cars headed to the parking lots near the fairgrounds. Cycling faster than the traffic was easy since the streets around the fairgrounds were largely grid-locked with cars inching along. Thankfully, the drivers maintained their cool and avoided the temptation to drive in the bike lane - as witnessed last year. I was able to scoot past them and arrive at the greenhouse intact.

My main assignment was climb up on a ladder and use a standard garden hose to spray the leaves of four small trees. The goal was to dislodge insect pests of various types: thrips, mealybugs, scale, spider mites, etc. After cleaning the plants, I use a hand-sprayer of dilute (less than 1%) peppermint and clove oil to coat the leaves. These essential oils are a natural deterrent - non-toxic to humans at low concentrations - to help keep the pests off of the plants. I've written about this subject in the past, and believe it's worth mentioning here again.

The small trees I cleaned treated today are: Passiflora lindeniana, Melaleuca citrina, olive, and lime.

Passiflora lindeniana, popular for its beautiful blossoms

Another assignment I enjoyed today was repotting a couple of small cycad plants. With an ancient lineage dating back to a time before the dinosaurs, the greenhouse has a small but respectable collection of these critically endangered plants. Many of them have struggled to thrive in the greenhouse. However, now a few of them have started to grow well. The hope is larger terracotta pots with well-draining sandy soil will encourage them further, and eventually produce cones.

Collection of endangered cycad plants

Finally, the plant coordinator for the greenhouse introduced me to an unusual plant that has just begun to produce flowers - Ceropegia sandersonii. The flower resembles an open parachute gentle wafting down to earth. It is unusual for its ability to trap flies, forcing the insect to remain in the blossom, unintentionally pollinating the flower as it tries to escape. Eventually, the blossom dries and the fly is able to escape.

New green and white flower of Ceropegia sandersonii, also know as the parachute flower, which is able to trap flies

Ceropegia sandersonii, parachute flower, climbing up a metal hanger

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