Tuesday, December 28, 2010

Monarch Madness

Liatris ligulistylis is a plant that no sunny garden should be without. Not only are the long purple wands of flowers attractive, but they are irresistable to monarch butterflies. Supposedly there is some kind of pheromone that this species makes that makes the monarchs so eager to visit. They linger, fly away, then quickly return, and seem to have great difficulty making a final departure. I like the fact that my school garden offers food to these hardy migrants, not only from the liatris flowers, but also from milkweed foliage for their caterpillars (I do check to make sure the various Asclepias species are not overwhelmed, and thus far there has not been a problem--the hideous bright orange milkweed aphids are more of an issue at times). Butterfly bushes (Buddleia davidii cvs) also are favored by the monarchs and many other butterflies in the school garden.

Arctotis venusta

Near the rudbeckia mentioned in the previous post, a few plants of Arctotis venusta did very well, despite a hot and dry summer. This annual species is native to dry areas of South Africa and Namibia, and its range includes mostly summer rainfall areas. I started the seeds indoors and set the plants in the garden in early summer, and they really took off in August and September. Unlike many Asteraceae, it appears that this species is self fertile, though not all seeds produced are fertile--fertile seeds are distinctly larger than the smaller infertile ones, when one drops them onto a hard surface their is a slightly different sound than with infertile seeds, which are all seed coat with nothing inside. The rather large flowers are moderately frost resistant, and of a peculiar light mauve/bluish sort of color, with a distinctive darker blue eye. The attractive grey green foliage is also quite unusual. Like most South African annuals, this species likes maximum sun and good drainage, and it is not fussy about soil. I don't know if it would resow, in any case I collected most of the seeds produced so I can enjoy more of it next year.

A Really Nice Rudbeckia

I got this floriferous perennial from a friend I know from my days at NYBG. She had it growing in her City Island (Bronx) garden for years, and allowed me to take a few clumps, which I planted in the school garden. She said it came via NYBG, probably from the native garden when we all worked there. I have not been able to figure out exactly which species it is, and have not seen it elsewhere yet, not even at NYBG. I presume it must be a southern species, possibly a rarish one. It is the best of the rudbeckias (and I have never met one that I didn't like) that I have grown in terms of neatness, good foliage, and floriferousness. The smooth dark green foliage is more attractive than the otherwise excellent, if overused, garden workhorse R. fulgida "Goldsturm", and the flowers appear later in the summer. It also does not get mildew, as R. triloba is sometimes prone to. The flowers are smaller than Goldsturm, and last a really long time, in fact there were still some flowers when frost finally arrived in November. This species seeds around a bit, but young plants are easily moved or removed as needed. It makes a bold statement in the garden and looks great when the students return for school in September.