Expand your plant palette. Two weeks ago I visited a friend, Mark Bridgen, who heads up the Long Island Horticultural Research and Extension Center for Cornell University. He's a plant hunter and breeder, and one of the highlights of my visit was seeing his new Alstroemeria (Peruvian lily). Mark was conducting trials of hardy varieties for our region (Zones 5-7). They typically bloom from spring till frost, making them a good filler for bare spots in the garden, and they're heat tolerant, too. The easiest way to get a repeat bloom is to pull the stems from the base of the plant after the flowers are spent. This encourages two buds to form; when you prune, you get only one. New shoots will emerge quickly from the rhizome. Alstroemeria does best in full sun - six hours or more - and you'll get more blooms if you can keep the rhizome cool. The best way to do this is to plant in a shallow hole and cover with a layer of mulch. Once you find the perfect spot, try not to disturb it; this will decrease bloom count. For information, go to http://alturl.com/cref4.
Time to ...
Trim to rejuvenate. The other day I cut back my 'Walker's Low' catmint. It was really looking tired after our long hot spell - but it's extremely drought tolerant. I cut the old stems back to the crown where new growth was sprouting. By doing this, I'll get another good flush of growth and flowers before fall. You can, too, if you trim now.
Think crocus! This isn't as crazy as it sounds in midsummer. Fall bulb catalogs will soon be out, and I want you to be ahead of the pack with the next garden craze: the crocus lawn. It'll wow anyone driving by, but also impress us as we drive up to our own homes in early spring. Why this craze? It's a way to get more color and interest from our gardens, even on small properties, very early in the spring. Also known as snow crocuses, these bulbs are planted in the fall amidst the grass and they pop up early enough that by the time you're ready to mow, their foliage will already be on the decline. The plants go dormant before the lawn is in its full growth. And here's a bonus: Squirrels don't usually eat these crocuses. We have masses of them at the Ambler Arboretum of Temple University, and they're breathtaking. Here are my top picks for lawn-planting: Crocus tommasinianus and variations on the species, var. roseus, 'Lilac Beauty,' 'Barr's Purple' and 'Ruby Giant.'
They sell out quickly, so order early.
Get to know your cooperative extension. Several people have written to me about diseased plants in their gardens, a common problem this summer because the winter was so mild. Some diseases can be deadly; others are just nuisances. If you're not sure what you're dealing with, you have several options. You can call your local extension office, go in person (with plant samples or cuttings of the diseased portions), or pack up those samples and send them off to be tested. Extension agents will analyze the cuttings and recommend treatment. When packing up your specimens, follow the instructions on the plant pathology page of the extension's website. You want to make sure the cuttings arrive in good condition for an accurate diagnosis. For information in Pennsylvania, go to http://plantpath.psu.edu/facilities/plant-disease-clinic and for New Jersey, http://njaes.rutgers.edu/pubs/plantandpestadvisory/.
Leave those wood piles alone. There's a new scourge in town called thousand canker disease, and it's deadly for black walnut trees. Carried by the walnut twig beetle, this slow-moving fungus affects first the branches, then the trunk. The disease was first sighted in our area in Doylestown last August and now is believed to be spreading throughout the region. If you use firewood, be sure to use only local trees. The State of Pennsylvania has banned the movement of firewood out of Bucks County and from states that have the disease - Arizona, California, Colorado, Idaho, Nevada, New Mexico, Oregon, Tennessee, Utah, Virginia, and Washington. Moving firewood is the number-one way tree diseases travel, so please discourage everyone you know from taking firewood out of the neighborhood. Because black walnut wood is so prized by woodworkers and others, thousand canker disease can really cause problems for the economy. So be savvy. Read up on plant diseases at http://alturl.com/tf2pv
Eva Monheim is a certified arborist, master floral designer, and fulltime lecturer in horticulture at Temple University Ambler; she is also an instructor at Longwood Gardens in Kennett Square. Contact her at emonheim@temple.edu
