Inside The New York Botanical Garden

Archive: March 2011

From the Library: Colossal NYC Potholes

Posted in From the Library on March 30 2011, by Plant Talk

NYBG pothole

Of course, we’re not referring to the potholes you might encounter this spring on the Mosholu Parkway or the Cross Bronx Expressway. We’re a botanical and horticultural research library after all, far more interested in natural history, so when we say potholes we mean glacial potholes.

This enormous one was photographed in 1913. Originally it would have been twelve feet deep, four to five feet in width, tapered at the bottom. And its earliest published description might have come from Nathaniel Lord Britton, first Director-in-Chief of The New York Botanical Garden, in the proceedings of the New York Academy of Sciences.

Dr. Britton told a meeting of the Academy, on June 5, 1882, that the above as well as other potholes were “brought to my notice by the late Professor A. Wood. They are located on the western bank of the Bronx River, about midway between Bronxdale and Williamsbridge…near the western end of a now dismantled and impassable bridge, with stone abutments, and in the northern part of a hemlock grove which fringes the stream for about a mile below. It is one of the most picturesque spots in the vicinity of New York City, and a walk along the little river from Bronxdale to Williamsbridge is always enjoyable.”

Housed in the archives of The LuEsther T. Mertz Library, this historical photo also accompanied “Pot-holes in The New York Botanical Garden”—an article by paleobotanist Charles Arthur Hollick, in the September 1913 issue of the Journal of the New York Botanical Garden, page 157.

“Pot-holes are bowl- or basin-like depressions in rock,” Hollick wrote, “caused by the abrasive action of gravel or cobble stones when churned around in the depressions by rapidly moving water. A pot-hole has its beginning in an irregularity or inequality in the rock bed of a stream, in which gravel or perhaps a single cobble stone or other rock fragment finds logdment. If the conditions are favorable, so that the foreign material is free to move and the current of the stream is sufficiently rapid to churn or swirl it around, the original inequality in the stream bed becomes deeper and more or less circular in shape, from the abrasive action of its contents, and a pot-hole is formed. A pot-hole, therefore, no matter where it may be located, is definite evidence that the rock in which it was excavated must have been, at some time, a part of the bed of a rapidly flowing stream.”

Aspiring Asparagus

Posted in Gardening Tips on March 29 2011, by Sonia Uyterhoeven

Sonia Uyterhoeven is Gardener for Public Education.

We eat different parts of plants. Some of the roots that we eat in vegetable gardens are carrots and radishes. Some of the leaves that we eat are lettuce and kale. Fruits are cucumbers and tomatoes. And stems….

In mid summer if you walk by a vegetable garden and see a patch of tall airy fern-like sprays of foliage and can’t put your finger on what it is – then it is simply a matter of timing.

You will recognize this vegetable in the spring as the shoots emerge from the ground before they grow to their full size. What is it? – Asparagus (Asparagus officinalis). By mid summer they have branched out beyond recognition and have an enormous amount of ornamental appeal.

Asparagus is a perennial (zone 2 to 8) that will last up to 15 years or longer in your garden. Make sure that the soil is properly amended with plenty of organic matter before you plant your asparagus since it will be there for a while.

Asparagus prefers full sun although it can handle part shade. Good drainage and rich soil is essential. It grows best in a pH between 6.5 and 7 but will handle a pH down to 6. If your soil is more acidic you will need to lime.

Asparagus can either be planted from seed or from 1 year old crowns (which is the norm). Plant the crowns (the area where the roots and the shoots meet on the plant) immediately so that it doesn’t dry out. If you can’t plant right away store the crowns in the refrigerator and mist occasionally.

Dig a trench for your plants on the edge of the garden where they will not shade out other vegetables – the foliage gets from 5-9 ft. tall. Plant the crowns 4 weeks before the last frost date in your area. Dig a trench 5 to 10 inches deep and generously amend with organic matter. Plant the crowns 18-24 inches apart in rows 3 feet apart.

Make a ridge in the middle of the trench and place the crowns on the ridge so that their roots spill over the edges. It will look like a row of octopuses sitting on a ridge. Cover with several inches of back fill and wait until you see growth before you continue to cover.

Asparagus is dioecious – older varieties such as ‘Mary Washington’ has male and female flowers on separate plants. The female plants expend energy producing seed and are not as productive. In the past people weeded out the female plants and kept the male. These days Rutgers University has produced all-male hybrids that are more productive. ‘Jersey Knight’, ‘Jersey Giant’ and ‘Jersey King’ are three popular varieties on the market.

The Rutgers hybrids should only be planted 5 inches deep. Older varieties are best planted 8-10 inches deep – they are less productive and run into problems if they are planted much deeper.

Do not harvest your asparagus for two years to allow them a chance to get established. During the third year you can harvest for 3-4 weeks and after that you will be able to harvest for 6-8 weeks. Harvest spears when they are about 6-10 inches long in spring.

Asparagus benefit from a good layer of straw mulch in the middle of the summer to keep weeds down and moisture in. Water during dry spell but otherwise they plants are fairly self-sufficient. Weed the bed at the end of the season and fertilize with compost or aged cow manure. Once the foliage dies back you can cut it down for the season.

Please Give a Hoot

Posted in Around the Garden on March 25 2011, by Plant Talk

Ann Rafalko is Director of Online Content.

Hello all! So I’ve heard from several sources that you guys are all just as excited as we are about the family of Great-Horned Owls that have just successfully hatched a nest of chicks for the first time since 2009! The owls are really amazing birds, and just one aspect of what makes the Garden such a special place.

Great-Horned Owl Chick

That said, just like any new family, the owls need a little peace and quiet. I received this email today from Jessica Arcate-Schuler, Manager of the Forest where the owls are nesting:

Please advise all visitors to stay on Azalea Way while viewing the Great Horned Owls nesting at the edge of the Forest. First and foremost, this is to prevent any disturbance to the owls and owlets. Secondly, to help steward the Forest by not trampling newly planted restoration plants, salamanders, and causing soil compaction. Notify visitors that the nest and male owl, when he is on his normal perch, are both visible from Azalea Way and can be seen with binoculars.

With the excitement of the owlets hatching, more and more people seem to be traveling to view our owls (I met a birder from Boston, this week!). For the health and well-being of the owls and the Forest, we appreciate your help.


So, please come to the Garden to see the owls! Please bring binoculars, wear sturdy shoes, and bring your camera. But, please give a hoot, and do not disturb the owls. We’re working on something a little special that should hopefully let people who aren’t able to come visit get in on the owl excitement, so watch this space. Happy weekend everyone!

Morning Eye Candy: Drizzle

Posted in Photography on March 25 2011, by Plant Talk

Everyone knows that April showers bring May flowers. But what do the drizzles of March bring? After a winter like the one we’ve had, March showers bring a gift that might be even more precious than May flowers: Spring’s first blossoms!

Drops on a Branch


Cornus mas

Cornus mas

Corylopsis sinensis var. calvescens

Corylopsis sinensis var. calvescens

Photos by Ivo M. Vermeulen.