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Entries in tall plants (2)


Chelone Obliqua: a Tall, Pink Perennial with Turtlehead Flowers 

HORT 218 Herbaceous Landscape Plants ~ Horticulture & Landscape Architecture - Purdue UniversityGardeners, who shop for plants only in spring, miss an opportunity to be seduced by the easy-care, cold climate perennial, Chelone obliqua. A late summer blooming plant, it has insufficient growth in early spring to draw the plant hunter’s attention. Even if one examines its label, there is little to attract because plant tag photography does this flower an injustice.

However, by reading the information on the tag, the astute gardener will notice that it is a tall growing, long blooming perennial that thrives both in sun and part shade. It reaches 23 to 35 inches in height [60 to 90 cm] has a wonderfully small spread of 18 to 23 inches18 [45 to 60 cm] and it blooms not only for a lengthy period but also at a time when most other perennials are waning.

I discovered this plant by accident. Seedling-sized plants were on sale at a ridiculously low price and I kept filling my basket with all of the pink perennials I could find. Of the hundreds that I chose, and then discarded because they did not please me, Chelone obliqua is one of the few that I kept. crept into my affection stealthfully. During the beginning and early summer, it remained unnoticed. Its deep green foliage did not project from far. However, just as I was beginning to dread that many plants were about to end their flowering, Chelone broke into bloom, unexpectedly. Its rich, deep-pink flowers and its tall, elegant shape were pleasing to behold.

Chelone obliqua is a neat, versatile plant that adds a lush background to the perennial border. Its height makes it a perfect candidate for the last row in the flowerbed, where its slow but steady growth adds texture, and form to a garden’s composition.

Up close, one may appreciate its polite lipstick-shaped floral buds that open into upward facing turtleheads. However, from a distance, this plant requires maturity before it can add its voice to the garden's chorus. When viewed at a length from the flowerbed, a young lone stalk of Chelone in bloom is difficult to notice; its flower bud is small and its shade of deep pink does not project effectively.  However, a mature clump, with a dense amount of flower heads, is impressive. is a disciplined perennial; it grows neatly and upright, with florets that are confined to the top spear- tips of its stalk, while its tight clump does not spread beyond three feet. When it reaches that width, not only is it impressive, in shape, color, and flowers, but it is also easy to propagate. In spring, its root ball may be sliced easily into many other plants. However, if propagated in late summer, or even autumn, the cuttings will regenerate into rugged plants by the following spring.

Do not be misled by its beauty. This is a tough, hardy perennial. On many occasions, when it would overwhelm me with pleasure, I would break off a few outside stems, at the point above ground where they grew away from the plant, and stick them into soft earth. They did not die. In fact, they began to grow roots imperceptibly and by the following season, the stems had generated into respectable plants.

This perennial shows better in the garden when several are planted within view of each other. One Chelone is impressive but subtle. Three Chelone, that can be viewed, all at the same time, have a more substantial presence that is enhanced by the rhythm of odd-numbered plants. have grown the species Obliqua and a variety called Hot Lips. There is no contest between them. I allowed Hot Lips three years to develop but it never grew into a satisfying perennial. The species, obliqua, grows taller, more floriferous, and richer in color.

Chelone Obliqua ia a versatile wildflower, native to North America. It grows under any pH conditions, in most soil types, and in most moisture levels. It performs well in both sun and part shade and blooms from late summer into mid fall. This plant is a northern gardener’s dream. It is a cold climate perennial, very easy-care, and it contributes structure, form, and beauty to the late summer landscape.

There is great benefit from using hardy plants native to North America. With absolute and total neglect from me, this perennial flourishes reliably in USDA Zone 4; and some sellers report that it is hardy to Zone 3. It is heat tolerant to USDA Zone 9.


Aconitum: Toxic Perennial if Taken Internally

Image courtesy of Van Hoorn Nurseries.Aconitum is one of several impressive blue perennials used as background plants in English style gardens. The tall pure blue varieties make nearby pink flowers so vivid-looking that I needed to include Aconitum in my own garden. However, my eagerness for them ebbed when I found these plants at the nursery with a cautionary sign hanging over them that read: this plant is poisonous. Naturally, I chose not to buy. There have always been children playing in or near my flowerbeds. I did not want to deliberately create a scenario that might endanger them.

This stately perennial, also known as Monkshood, is one of the most poisonous of plants. Since ancient times, people have known that it is toxic and have used it as a weapon by coating their spear and arrow heads with its strong poison in order to kill wild animals. Some gardeners believe that this popular garden plant has such a distinctive and unpleasant taste that cases of accidental poisoning are rare, though known. However, all parts of the plant are toxic if eaten and its roots may be fatally mistaken for edible crops if left lying around. Even the abraded skin of a gardener can absorb a dangerous dose of its poison.

Image courtesy of Glenlea GreenhousesSome brave gardeners feel that handling the plant itself is not a problem and there is no reason not to grow it. I argue that if Aconitum were to be planted in ample-sized flowerbeds, such as those on large estates, one might not be so anxious about accidental poisoning. However, in tight urban flowerbeds, where gardeners often collide with their flowers, the possibility of a fatal accident is real.

Here are some of the symptoms of Aconitum poisoning: Burning of lips and mouth, numbness of throat, intense vomiting and diarrhea, muscular weakness and spasms, weak pulse, paralysis of the respiratory system and convulsions. Did you ever expect to read something as gruesome as this in a gardening blog?

Nevertheless, if a reader is determined to grow Aconitum, here is what one needs to know: This tall plant grows stalks that are so strong they do not need staking. There are many varieties of Aconitum, ranging in heights of 18 to 48 inches tall. The color palette includes white, pink and blue. The tall blue varieties are the most desirable because of the purity and intensity of their color. This perennial will grow in full sun or light shade but flowers get floppy with reduced sunlight. Aconitum performs best with a minimum of six hours of full sun every day. This plant blooms in late summer to early fall and is happiest in moist, fertile soil.

As soon as the first flowering flush is over, cut the bloom stalks to the ground to prevent seed development. This will encourage re-blooming later in the summer. Always wear gloves, long sleeved tops and long pants when gardening near this plant. Avoid placing Aconitum close to vegetable gardens or children’s play areas. Depending on the variety selected, this plant will grow in zones 2 to 8. I cannot suggest specific cultivars because I do not grow this species. As breathtaking as this perennial may be, the sounds of children playing touches me deeper.