Garden Notes

Quince trees
Quince trees were once plentiful on the Island. Photo by Susan Safford

Dogwood: a second look

By Abigail Higgins - September 13, 2007

In a previous Garden Notes (July 5) I mentioned that the Cornus kousa outside our bedroom window failed, due to caterpillar damage as I supposed, to have much bloom this year. While reading a borrowed copy of "Dogwoods," by Paul Cappiello and Don Shadow (Timber Press, 2005), I came across additional information about kousas. It concerns alternate year bloom, a concept in dogwoods that is new to me, but which perhaps other dogwood growers have noticed.

In the book on page 145, two photographs of the same kousa dogwood taken in different years demonstrate that the tree has an alternate-year bloom habit, with only one limb flowering in the off year. That is what our kousa actually did this year, bloomed well on only one branch, while it was also heavily hit by caterpillars overall. I ascribed the lack of bloom to the caterpillars when alternate-year flowering may have caused it.

Fruitful harvest


The year 2007 has seen heavy crops on beach plums. A trio of good cooks, who have been picking and making beach plum jam, were having a discussion in my kitchen Sunday morning about their methods and where they had gathered. A problem this year is that the crop is one with no excess wateriness, bountiful, and ripe early - possibly due to the dry conditions causing a good fruit set in spring- so pectin levels are low.

With low pectin the jam or jelly will be more like a delicious syrup than a spreadable preserve. The standard remedy is to throw a handful of green beach plums into the jam kettle along with the really ripe ones. If you lack green beach plums a commercial pectin product can be added, or you could try chopping or grating a pectin-rich apple or quince into the jam kettle.

On its own, the fruit of the quince, Cydonia oblonga, is used for making pies, sauces, and marmalade-type confections. In the cuisine of Spain, and eaten also in Latin America, dulce de membrilo is very much the same thing as quince marmalade. Sad to say, many venerable Island quince trees, ones I knew in my childhood, have been destroyed or have fallen victim to development. Many people have never seen one.

Look for a small tree, often picturesquely shaped, that might at first be taken for an apple. At this time of year there is the gorgeous, perfumed golden fruit, round to oblong with a somewhat irregular shape, often to be found wearing a whitish, felty covering that is easily wiped away. In spring, after the apples bloom, the quince blossoms with beautiful pale pink, five-petaled flowers, a cluster of prominent stamens in the center. It is true quince is not a fruit one eats out of hand. It is still a wonderful home orchard and landscape subject, due to its small scale and picturesque shape, often like a life-sized bonsai.

Unlikely poisons

As many gardeners and cooks prepare to can and freeze, and to put up preserves, I thought it might be timely to mention food that you would definitely not want to have ending up in the preserving effort. It is a great year for berries; please be sure to correctly ID any berries collected for jam making. The climbing nightshade (Solanum dulcamara) is a danger to children especially. Wildly beautiful in this season with glowing ruby fruits, it is often found twining in other berried bushes like viburnums. Many plants commonly found in Island gardens or growing wild have properties capable of making us sick. And more are being added all the time as the nursery trade casts its net far and wide in search of colorful tropicals and exotics to spice up our plantings.

What would gardeners do without Timber Press! I had pulled out my copy of "Common Poisonous Plants and Mushrooms of North America," by Nancy J. Turner and Adam F. Szczawinski (paperback 2003, 311 ppg.) after reading the column of my colleague Lynne Irons concerning the baffling skin irritant problem. Appendix 3 is entitled "some common plants causing skin irritation and/or mechanical injury," so I thought I would start there. Hmm, there are four pages of plant names - and what is surprising is how many are commonplace plants, that gardeners would come in contact with literally, and frequently: privet, bleeding heart, cardinal flower, euphorbia, tomato, achillea, English ivy, to mention just a few.

(I had purchased "Common Poisonous Plants..." to add to my references on mushrooms, but discovered that it contained much more than merely a good section on bad fungi. There are four other chapters, of which the first is all about poisoning, treatment, and types of plant poisons. The second is the mushroom chapter. However, it is the chapters on poisonous plants, including algae, of wild areas (Chap. 3); poisonous garden and crop plants (4); and poisonous house plants and plant products (5) that contain the real eye-openers. The volume closes with six equally interesting appendices, glossary, references and a thorough index.)

Then I started reading more seriously, and things only get worse. It is not only gardeners coming into contact with plant irritants who are at risk, but also cooks and diners. The charming custom of using flowers in cookery and garnish is potentially risky. Knowledgeable chefs would do well to have a copy of a book like "Common Poisonous Plants..." to refer to, especially now that we routinely have so many individuals on medications or with compromised immune systems. Those pea tendrils garnishing your gourmet dinner? Contain toxic amino acids, mildly poisonous, as is almost everything about the bean, pea and vetch family members, except the actual seeds. And even the culinary seeds of commonly consumed legumes like favas, chickpeas, and soybeans can present problems unless correctly soaked, parboiled, fermented, or otherwise modified to neutralize the toxic elements.

Often the plant poisons work by blocking something: like uptake of iodine by the thyroid gland (Brassicas); by tying up something, like oxalates affecting calcium thereby creating a calcium deficiency; or by destroying something, like red blood cells (fava beans). But plants are amazing. Here is the array, culled from chapter one, of poisons they make: alkaloids; glycosides; oxalates; phenols; alcohols; proteins, peptides, and amino acids; resins and volatile oils; phototoxins; and carcinogens. Whew!

By all means follow in the footsteps of Euell Gibbons and become acquainted with the local edible flora, but beware that innocuous plants have surprising aspects.