Let’s catch up on some plant and garden “readlings” this week while we wait for next month’s pea-planting milestone…
Invasive plants banned
Five kinds of honeysuckle are the latest plants to be banned for sale in Pennsylvania after being deemed harmfully invasive, earning spots on the state’s Noxious Weed List.
The state Department of Agriculture’s Controlled Plant and Noxious Weed Committee last month voted to ban the amur, Morrow’s, Tatarian, Bell’s, and fragrant (Standish) types of honeysuckle from sale in Pennsylvania. (Note that this doesn’t include native trumpet or coral honeysuckle varieties such as ‘Alabama Scarlet,’ ‘Major Wheeler,’ and ‘Cedar Lane’ or other honeysuckle species and hybrids such as ‘Gold Flame,’ ‘Serotina,’ ‘Scentsation,’ and ‘Winchester.’)
The committee also voted to add starry stonewort – an algae that can clog waterways and interfere with fish breeding areas – to the Noxious Weed List.
The additions bring the Class A list to a total of 20 plants (ones that can possibly be eradicated) and the Class B list to a total of 38 (ones that are too widespread to feasibly be eradicated). Most plants on these lists are what most people consider to be “weeds,” such as Japanese knotweed, thistle, poison hemlock, kudzu, giant hogweed, and such.
The latest action continues a state crackdown on invasive plants that began in late 2021.
Since then, Pennsylvania has banned the sale of several popular landscape plants, including flowering (callery) pear trees, burning bush, common and glossy buckthorns, chocolate vine (Akebia), four types of privets (Japanese, border, European, and Chinese), and Japanese barberries (except for four sterile varieties in the WorryFree series: Crimson Cutie, Lemon Cutie, Lemon Glow, and Mr. Green Genes).
- Read more on previous plant bans
Although gardeners aren’t being required to remove banned plants from their yards, the Ag Department is recommending their removal to stop continued, unwanted seeding into the wild.
Many of the newly banned landscape plants are being phased out of sale.
Japanese barberries, for example, will be banned from sale as of Oct. 3 this year, while flowering pears will be banned as of Feb. 10, 2024.
Burning bush and the four banned privets have a grace period until Jan. 10, 2025.
The honeysuckles and starry stonewort will be banned 60 days after notice of the Ag Department’s action is published in the Pennsylvania Bulletin, which is expected to be by early this spring.
Although the above plants can be sold until the above cutoff dates, the Ag Department is discouraging gardeners from buying them, instead recommending native or non-invasive alternatives.
- Read George’s column on native alternatives to invasive plants
Hershey Gardens is almost done with its re-do of its 20-year-old Children’s Garden.
Facelift of Hershey’s Children’s Garden
Renovations to Hershey Gardens’ 1½-acre Children’s Garden are nearly complete, and the 20-year-old interactive garden is on target to sport its fresh look by spring.
“We’re waiting on the delivery of some additional things to install and replace,” says Gardens’ spokesman Anthony Haubert. “Once that happens, we should be complete with all the renovations. We’re aiming to be done by the end of March or beginning of April.”
The work has included new plants, new cedar for the bird blind, repointed stone work, new raised beds in the Hoop House, and fresh paint throughout.
In the works is a revamped treehouse (being reimagined to a rainforest theme with thatched roof, cocoa-pod accents, and a climbing pole), a new boat play structure, and a new wooden bridge in the River Banker’s Picnic area.
The early-spring finish date coincides with the time gardeners get antsy for Hershey Gardens’ vast spring bulb display.
Peak bulb bloom typically runs from mid-April to early May, depending on each season’s weather.
“It’s always a guessing game as to when that will happen,” says Haubert. “We tell individuals who inquire – and we get a lot of inquiries beginning mid-March – to check our website and social media pages for updates on the blooming of the tulips.”
This past fall, staff planted nearly 26,000 new bulbs. That included 1,500 new daffodils around the Conservatory and the rest assorted types of tulips around the Conservatory, in the Children’s Garden, and the bulk in the Seasonal Display Garden.
Also over the winter, Hershey’s staff replaced overgrown potted palms in the conservatory’s main-entrance atrium with more compact foxtail palms.
This sedge, known as wood’s sedge, was the top performer of 70 species and varieties in Mt. Cuba Center’s new trial.
The best sedges
Delaware’s Mount Cuba Center is just out with results of its latest plant trial – this time exploring 70 different species and varieties of sedges (Carex) over four years of evaluation.
Sedges are grass-like perennials that have come into vogue lately, not the least because deer seldom browse them.
“(Sedges) are quickly becoming favored by homeowners and horticulturists alike, thanks to their beauty, utility, and overall minimal maintenance requirements,” says Sam Hoadley, Mount Cuba’s manager of horticultural research. “The diversity of the genus is outmatched only by the wide spectrum of habits in which they grow. From shady wetlands to coastal dunes, you can find a (sedge) to grow and thrive there.” Many sedges are U.S. native plants, and as Mount Cuba’s trial report points out, most can even be used as mowable substitute for traditional lawn grass.
Mount Cuba trialed the 70 sedges in both shade and sun in average garden soil. In the last year of evaluation, staff mowed the sedges every two weeks to assess their potential as a lawn substitute.
The foot-tall, green-bladed, native wood’s sedge (Carex woodii) clocked in as the trial’s top performer. Hoadley says it excels in both sun and shade, offers a carpet of straw-colored flowers from April to May, and was the trial’s top-performing mowable sedge.
The remaining top 15 sedges in the trial (after wood’s sedge) were: Cherokee sedge (Carex cherokeensis), common brome sedge (Carex bromoides), Hayden’s sedge (Carex haydenii), upright sedge (Carex stricta), Emory’s sedge (Carex emoryi), long-beaked sedge (Carex sprengelii), Pennsylvania sedge (Carex pensylvanica), Pennsylvania sedge ‘Straw Hat,’ Muskingum sedge ‘Little Midge,’ white-tinge sedge (Carex albicans), James’ sedge (Carex jamesii), Muskingum sedge ‘Oehme,’ fringed sedge (Carex crinita), Leavenworth’s sedge (Carex leavenworthii), and plantain-leaf sedge (Carex plantaginea).
Ramps are onion-like native plants that have become foodie favorites lately.
Raiding the ramps
Ramps – those onion-like plants often found growing wild in Appalachia’s woods – have become so popular in foodie circles lately that concern is mounting over their over-harvest.
A new Penn State study finds that if ramps gatherers would wait a month longer before harvesting, ramps colonies would rebound much better.
Also known as wild leeks, these strappy-leafed plants have been locally popular for hundreds of years for their garlic-like aroma and onion-like flavor. Both the leaves and underground bulbs are edible.
Ramps’ demand – and value – has gone up sharply in the last few years as they’ve become darlings of foodies and restaurant chefs. The price increases have fed a sharp increase in gathering from wild colonies.
Enter Penn State, which studied ways of conserving this “cultural keystone resource.”
“With even modest harvests from ramp patches, it can take years and years for those plant populations to rebound,” said Eric Burkhart, a Penn State associate professor of ecosystem science and management.
Penn State researchers found that by pushing back peak harvests a month from the usual harvest period of March 1 to May 30, plants can increase their yield significantly.
“If foragers would just wait a little longer,” says the study’s lead researcher, assistant professor of biology Sarah Nilson, “they can actually collect the same weight of ramps with less effort because the plants are larger. We will be trying to promote this little saying: Fewer ramps per pound is more ramps in the ground.”
Nilson adds that it’s best to wait until the plants have developed at least three leaves before harvesting.
Ramps are perennial plants that can be grown in home gardens as well, although they do best in moist, shaded spots – unlike traditional onions and garlic.
British plant developers have produced a tomato with purple flesh as well as purple skins.
Purple tomatoes
Gardeners have long been able to grow tomatoes with purplish skin, but a pair of British researchers have developed the world’s first cherry-type tomatoes that are deep purple throughout.
The true-purple tomatoes were genetically engineered at laboratories in England, using a pair of snapdragon genes as the genetic “on switches” that trigger the tomatoes to produce purple pigments in the fruits’ flesh as well as their skins.
Professors Cathie Martin and Jonathan Jones formed a company called Norfolk Plant Sciences to produce and sell seeds.
The company got U.S. Department of Agriculture regulatory clearance last fall to begin selling the new variety in the U.S. Seeds aren’t available yet, but interested gardeners can sign up for them through Norfolk’s Big Purple Tomato website.
Besides the striking look of the fruits, the company says the purple tomato has a longer shelf life and improved nutrition, especially the antioxidant anthocyanin, which has anti-inflammatory properties and can reduce the risk of cancer and heart problems.
Seeds could be available by later this year.
