George's Current Ramblings and Readlings

The Best – and Worst – Times to Do Things Around the Yard

March 1st, 2022

   Some gardening jobs can be done most any time.

Cutting the ornamental grasses with a power trimmer.

   But others need to happen at certain times if you don’t want to, say, freeze your tomatoes by planting them too soon or cut off your hydrangea flowers by pruning them at the wrong time.

   As we approach another new gardening season, it’ll help to know when to do what. Here’s a look at the best times and worst times to do a dozen key tasks in Pennsylvania yards:

Pruning

   Best time: For spring-flowering trees and shrubs, right after they’re done blooming. For summer-flowering trees and shrubs, first thing in early spring. For shade trees, late winter when leafless. For evergreens, early spring through mid-summer.

   Worst time: Fall. Everything should be left alone to prepare for winter’s cold then. Plus, you’ll cut off the already-formed flower buds for next year by pruning spring-blooming shrubs and trees in fall.

Fertilizing

   Best time: Spring and early fall – right before periods of good growth.

   Worst time: Any time the ground is frozen and during hot, dry weather in summer.

Planting

   Best time: For woody plants and perennials, end of March through May and between Labor Day and end of October in fall. For frost-sensitive annuals and vegetables, mid-May through early summer.

   Worst time: Winter and during a heat wave in summer. For borderline-hardy species, spring is a better time to plant instead of fall (more time for the roots to take hold).

Digging soil

   Best time: Spring – after the soil has dried. Or any time in summer or fall.

   Worst time: Any time the soil is wet or frozen.

The Latest in Gardening Research: Hedge-Trimming Robots, Super Roots, and Milkweeds of the Future

February 22nd, 2022

   Let’s catch up this week on some of the latest gardening research that might impact how we grow…

The European TrimBot2020.
Credit: Elsevier/ScienceDirect

A Hedge-Trimming Robot?

   We already have robots that vacuum our floors, mow our lawns, and even weed our gardens, so is a robot that trims our bushes and hedges next?

   Researchers in Scotland, the Netherlands, Germany, and Switzerland are evaluating a prototype hedge-trimming robot called the European TrimBot2020 that’s a wheeled machine fitted with eight cameras and a robotic arm with trimmers at the business end.

   In its first European real-world trial, TrimBot2020 was assigned to trim boxwoods into three different shapes – spheres, cylinders, and cubes.

   The initial results were underwhelming, according to a paper in this month’s issue of Biosystems Engineering.

   In both 3D computer assessments and evaluations by 10 humans, the best rating TrimBot2020 could muster was 3.1 out of 5.

   “The poor trimming performance, in particular for cylindrical and cuboid shapes, indicates that the trimming result of the mobile robot is not yet accurate enough for practical application of trimming complex shapes,” the researchers concluded.

   They added that the trial was helpful, though, in identifying “bottlenecks and weak points” to tweak TrimBot’s future performance.

   Automated plant-trimming machines already are used in some nursery productions, but those use GPS to trim mechanically without any sensory feedback.

   The trick in developing a robot for garden settings is figuring out how to navigate varying terrain and how to have a robot assess how it’s doing as it manipulates the bushes into the desired shapes.

The Quest for Bigger, Better Roots

   Research that turned out more promising came from Penn State University, where researchers isolated a genetic trait in corn and wheat that causes their roots to penetrate better into compacted soil. The trait could lead the way to new varieties that grow and yield better.

2022 Garden Trips: Hoping for “Normal” Again

February 15th, 2022

   Will this be the year when we can finally get back to traveling again without worrying about omicron variants, antigen tests, quarantines, and last-minute cancellations?

Some of the bulb beds at the Netherlands’ Keukenhof garden… one of our trip stops this year.

   I’m hoping. And assuming the best, Lowee’s Group Tours, Collette Vacations, and I have put the finishing touches on our 2022 lineup of garden-themed trips.

   Things have been so uncertain for two years now that it’s almost hard to remember the “good old days” when we could just go.

   It’s been an adventure even getting this far with the new planned trips. We normally have details ready on the whole lineup the fall before, but this year, Jo and Chrissie at Lowee’s have been pounding their heads trying to get confirmations and prices on everything.

   Although things still could change, we’re as ready as we can be with a 2022 series that will include a pair of European trips, another round of popular home-garden tours, five day trips to the 2022 Philadelphia Flower Show (outdoors again in June), and multi-day trips to see gardens of New York’s Hudson Valley, gardens of the Midwest (St. Louis, Nashville, Louisville), and a Christmas-time visit to North Carolina’s Biltmore and Tennessee’s Smoky Mountain National Park, Gatlinburg, and Pigeon Forge.

   I’ll be doing a free, online PowerPoint presentation with photos, details, and pricing tomorrow, Wed., Feb. 16, at 6:30 p.m. You’re invited to join. You just have to register in advance to get the log-in address and instructions.

   If you’re interested, click here to get the PowerPoint Zoom link from Lowee’s.

   I’ve also posted details on my Talks and Trips page.

   Or you can go directly to Lowee’s Garden Series website page, where you can see the itineraries and even book trips directly online.

   Or you can go the old-fashioned route and just call Lowee’s Group Tours at 717-657-9658 (or toll-free 1-888-345-6933) or email CKelly@Lowees.com.

   Here’s a quick rundown on where we’re planning to go and when:

   Netherlands and Belgium River Cruise, April 18-April 29, 2022

   We’ll see the stunning Dutch bulb fields, the amazing Keukenhof bulb gardens, and the once-every-10-years Floriade horticulture expo in this 12-day tour of the Netherlands and Belgium, which includes a seven-day river cruise. We’ll visit the Dutch towns of Arnhem and Middelburg, the Belgian cities of Bruges, Ghent, and Antwerp, and tour the Dutch windmill village of Kinderdijk, the huge Aalsmeer Flower Market, Amsterdam’s botanic garden, and a working bulb farm. Prices start at $4,999 per person double, including airfare, the cruise, hotels, admissions, and 26 meals.

No Winter “Wow,” but the 2022 Philadelphia Flower Show Will Happen

February 8th, 2022

   Cabin-fevered gardeners normally would be gearing up by now to visit the world’s biggest and oldest indoor flower show, which usually takes place in early March just two hours down the turnpike from Harrisburg.

This artist rendering shows the planned entrance to the 2022 Philadelphia Flower Show.
Credit: Pa. Horticultural Society

   But in case you’re wondering why you’re not hearing much about it, the Philadelphia Flower Show for the second straight year is taking place outside in June.

   To be specific, the 2022 show is scheduled for June 11 through 19 in the same place it was held last June – over 15 acres in south Philadelphia’s FDR Park.

   Lowee’s Group Tours and I will be offering five daily trips to the show June 13-17. Two of them will be show-only offerings, while three of them will include morning tours of three different Philadelphia-area public gardens before heading over to the Flower Show (Fairmount Park/Shofuso Japanese Garden, Morris Arboretum, and Chanticleer). See details on all of the trips here.

Read George’s PennLive.com report, with photos, from the 2021 first-time-outside Philadelphia Flower Show

   A lot of people (me included) were hoping the show would go back to its good, old, indoor, end-of-winter self after a year when COVID forced it outside for the first time in its 193-year history.

   But as people continued to get infected with COVID, the Pennsylvania Horticultural Society’s show planners eventually had to make a decision. The continuing uncertainty carried the day.

   “The whole driving force is COVID and the unknowns from it,” Sam Lemheney, PHS’s chief of shows and events, told me when the show pulled the plug on the return-to-inside idea late last September. “We have to decide so far in advance to have everything ready and have plants growing in the greenhouses. There are still way too many unknowns and potential complexities with going back inside the Convention Center. We did it last year outside and figure we can do it again… and hopefully make it better.”

The Best New Trees and Shrubs of 2022

February 1st, 2022

   Five hydrangeas with new twists, a compact new native Virginia sweetspire, and a “baby brother” to the popular ‘Green Giant’ arborvitae are among the best new trees and shrubs hitting the market for the 2022 growing season.

Hydrangea Let’s Dance Can Do!
Credit: Proven Winners

   Growers, local garden centers, and other plant experts picked the following dozen woody plants for the four-part, best-new-plants series I compile each year.

   Today’s best new trees and shrubs of 2022 is the final installment of this year’s series.

   Part one on best new edibles of 2022 appeared on Jan. 11, part two on best new annual flowers of 2022 appeared on Jan. 18, and part three on best new perennial flowers of 2022 posted last Tuesday, Jan. 25.

   Some of the following new tree and shrub varieties are available online and in some plant catalogs. Most also will be available in local garden centers beginning in April.

   The details:

Hydrangea Let’s Dance Can Do!

   Of all the many new hydrangeas introduced in the last few years, Proven Winners’ Natalie Carmolli says this one really stands out for its gobs of baseball-sized flowers that keep coming and coming – right to the end of the season.

   “It’s a reblooming machine,” she says. “We knew this plant was special when we released it, but it keeps surprising us with its outstanding ability to rebloom.”

   Carmolli says Can Do’s “secret” is that it sets flower buds along the entire length of each stem, not just at the tips.

   Although Let’s Dance Can Do looks like a common big-leaf hydrangea with rounded blue-violet or pink flowers (depending on soil acidity), it’s actually a type of mountain hydrangea. Mountain hydrangeas have winter-hardier flower buds than most big-leaf types, meaning less chance that winter will kill flower buds (a key answer to the question, “Why didn’t my hydrangeas flower?”)

   Let’s Dance Can Do plants grow three to four feet tall and almost as wide, its leaves turn a purplish shade in fall, and an ideal site is one with morning sun and afternoon shade.

Oakleaf hydrangea ‘Snowcicle’
Credit: Plants Nouveau

Oakleaf hydrangea ‘Snowcicle’

   Another new twist in hydrangeas is ‘Snowcicle,’ which is a native oakleaf type that’s unusual because it has double-flowering blooms.

   Angela Treadwell-Palmer, founder and co-owner of Alabama-based Plants Nouveau, picks this as her favorite new-for-2022 woody plant for its “incredibly long, double-flowered panicles and strong stems that set it apart from all of its predecessors.”

   ‘Snowcicle’s’ summer-long blooms are 12 to 14 inches long and age from creamy-white to a showy combination of rose-red, olive-green, and cream. The strong stems eliminate flopping, which is common on most oakleaf hydrangea varieties.

   ‘Snowcicle’ plants grow four to six feet tall in full sun to part shade and develop a fall foliage color that ranges from deep wine to burnt orange.