City Gardener

When cleaning my home or work space  doing the drains  is the dirtiest chore on the list. Almost all of the dirt and grime funnels down through the drain. If the drain is clogged, civilization as we know it, stops.  Today my task was to clean window sills and ...drains. The University of Minnesota Conservatory Greenhouse, where I've been volunteering, continues its summer push to deep clean the surfaces and plants to help keep them free of pests and diseases. Integral to a thorough job of cleaning includes lifting the drain grates and flushing out the accumulated soil and organic muck (dead leaves, seeds, etc.). Hiding out of sight under the grates, the muck is potentially a fertile reservoir of pest eggs and bacteria.  There were approximately a dozen drains in the four greenhouses of the Conservatory. Each drain consists of a heavy cast cast-iron basket covered by a round iron grill. I lifted, brushed, and washed each component. While I was working from drain to dr...

I can't begin to imagine the number of times I've encountered a complicated problem and then search for a complicated solution, while a simple solution would have been just as good. Today at the University of Minnesota Conservatory, where I volunteer, the greenhouse staff are continuing their push to treat and restore plants which have become threatened by pests. I was assigned the task of using a sharp spray of water from a hose to knock pests off from the leaves of plants. It is a simple physical means of control. No chemical poisons, repellents, or expensive predators are involved. While I walked around the greenhouse looking for infested plants to douse, I spotted this blooming gem. It has the genus name Hippeastrum, and is in the same family as the common amaryllis plant. Hippeastrum, in the same family, Amaryllidaceae, as the common amaryllis plant A sharp spray of water was used to knock of scale and mealybug insects from the leaves of two dozen plants. While on the t...

It is said the work of a gardener is never finished. This old dictum certainly applies to the greenhouse of the University of Minnesota Conservatory, where I've been volunteering. Since space in the greenhouse is limited, and the number of plant species large - 3000 or so - there is the necessity of keeping plants at a size able to fit the space. Cutting and tying the plants to control their growth is a bit similar to surgery in the sense that some parts get cut off, and some parts get tied back. Today, one of my tasks was prepare all the shears and handsaws to be sent out for professional sharpening. The blades all had to be scrubbed free of debris and sticky sap, then wiped with alcohol to disinfect the surfaces. The tools will be delivered to a local shop where garden implements are sharpened. Another task was to control the direction of growth of a couple of small trees in the desert room of the greenhouse. These small trees (the frankincense tree Boswellia sacra, and Moringa p...

The plants in the greenhouse of the University of Minnesota Conservatory, all 3000 of them, are now well into the growing season. The sap is rising and new growth is bursting up the stems. All this tender new plant material is a feast for plant-eating insects. Mealybugs, scale insects, thrips, and other species are multiplying in numbers by the day. If not kept in check, the result would be withering leaves from the insects, and sooty black mold which thrives on their poop. To combat these many critters there are tools to reduce, but never eliminate, their numbers. Today, my chore as a volunteer at the greenhouse is to use a simple soap solution and a sharp spray of water to physically knock the insects off from the surfaces of the leaves. It took me about 3 hours to treat one bench of plants; there are approximately two-dozen benches in the collection, spread across 4 different climate-controlled rooms. Especially in the growing season, it takes dedicated persistent effort to keep the...

What could possibly go wrong? Today at the U of M Conservatory Greenhouse where I volunteer, I was assigned the task of watering the plants in two of their four large rooms, the rooms for tropical and subtropical plants. These two rooms house hundreds of threatened and critically endangered plant species. The finger test The time honored finger test: insert your finger up to the first knuckle or two into the soil of any plant pot, if it feels dry water the soil thoroughly, if it feels damp leave it alone - don't drown the plant roots. It sounds like a mom-ism , but there truly is a sweet spot for dampness of the soil in a plant pot. Too dry and the plant withers; too wet and the roots rot. Basic energy economy of all plants Above the soil surface, plants makes sugar:  Sun's Energy + CO2 + Water  =>   Sugars + O2 Below the soil surface, roots use the sugar: Sugar + O2  =>   CO2 + Water + Energy to absorb nutrients and transport of water for the leaves and ...

 It is an adolescent instinct to make everything in life about yourself. For example, at the university greenhouse where I volunteer, two staff members have recently been promoted to new positions. I thought, initially, that it would be a fine idea to give them farewell cards that I made. As a personal touch the cards would feature one of my own photos of forget-me-not flowers, with its implicit message. I intended to include inside the cards a packet of forget-me-not  seeds. Clever, no?  I could even make it seem more inclusive of everyone in the department if I wrote a comment saying forget-us-not  rather than forget-me-not . What could be more friendly than the presentation of these pretty blue flowers?  I'll address the problem with my thought further below. But, put that aside for the moment and let's carry on with the plan. Forget-me-not flowers (the photo taken on our recent visit to Muir Woods, CA) Due diligence To ensure the flower seeds were going to b...

Surprised by the unexpected arrival of springtime this year, I suddenly recognized the opportunity to revive the balcony garden of our apartment. For the past two years the balcony has laid fallow, because I was out of town for weeks at a time. This summer, I'm here for the duration of the growing season and the balcony garden is back with a vengeance. The advantage of grasses I've  previously described my choice of plants for the balcony. But to summarize, the space is often challenged by intense afternoon sun and heat - sometimes up to 125F - reflecting off of the glass windows; the wind up here on the 13th floor can tear apart any plant stem that isn't firmly staked; and the entire balcony is steeped in deep shade until 1:00 in the afternoon when the direct sunlight slips past the edge of the balcony ceiling. Grasses offer the advantage of being tolerant to drought, adapted to wind, and easy to manage. I like how they soften the hard edges of the cityscape. Because this...