"When the frost is on the pumpkin..."

The frost is on the pumpkin! Twenty- four degrees was the reading on my thermometer on two consecutive mornings this week. Even hit twenty-eight in Doylestown. So the frost is on the pumpkin. This “killing frost” in the mid-twenties takes out all of the tender annuals… weeds and crops. Cold hardy plants carry on.

The picture shown here is a broccoli leaf and the heads that are part of this plant are still in good shape. In fact, one reason to plant fall maturing crops in the cabbage family (cabbage, cauliflower, broccoli, Brussels sprouts) is that they hold so well in the cool/cold temperatures of fall. Spring planted crops of the same species are forced to mature in the heat of late spring and early summer. They often go from “prime condition” to “over-the-hill” in a matter of days, especially when temperatures spike into the high eighties. I’d rather let Mother Nature hold them for me, naturally.

Forgot to plant you fall crops? Perhaps our local farmers can come to the rescue. As I visit local vegetable farms I see beautiful fields of fall vegetables. And, I know that bushels of winter squash are stored away from the freezing temperatures, just waiting for you to make pumpkin pies, baked squash and other fall specialties. I even know a local sweet potato grower who has several varieties of this nutritious root.

Turnips, rutabagas and parsnips are not everyone’s cup of tea but if you have not tried the farm-fresh version of these root vegetables recently consider giving them a try. Maybe next year they will be part of your fall garden, too.

Want more information on the culture of fall vegetable crops? Penn State’s brand new Vegetable Gardening publication is a great place to start.

PS For a wonderful reading of James Whitcob Rileys' poem, see this.

Jack Frost, Garlic and Cover Crops.

Rumors of frost were heard in northern Bucks County last Saturday (Oct 23) but for most of Southeastern PA the growing season continues uninterrupted. In fact, even where light frost occurred, as in my backyard, I still see many cold sensitive plants surviving. My fancy new minimum/maximum thermometer at the Extension office in Doylestown says 35 degrees F is as low as it’s been here.

So, it is clear we have not had that killing freeze that signals a definite end to many aspects of gardening. But official, long-term records tell us that we are on borrowed time… the median (equal number of occurrences on both sides of the question) frost date in Bucks County is October 6.

Sure enough the tomatoes and peppers that are still hanging on out there look pretty rough. The accumulation of summer diseases combined with short days and very cool nights makes most of us yank them out of the garden. In fact, smart gardeners ruthlessly pulled these plants a month ago and planted lettuce, spinach, broccoli rabe and other late season crops. Or maybe you even sacrificed the late season tomatoes altogether in return for a fall crop of broccoli, cabbage and cauliflower by transplanting these “cole” crops in late August or early September.

Even if you waited until now, there are a couple final crops you might consider. Cover crops and garlic.

Cover crops are plants that we establish to protect soil from compaction, to soak up leftover nutrients and to build soil organic matter. The most common fall cover crop in our area is rye. Not ryegrass but cereal rye, sometimes called winter rye. It germinates quickly in the warm, fall soil and makes a vigorous overwintering cover that resurges in the spring. In fact, you have to prepare to manage this cover crop or it will become a beast that is hard to incorporate. Plan to spade it under in April before it begins to bolt and go to seed. You’ll be rewarded with a great shot of soil organic matter, nutrition and biological activity. Rye is not the easiest seed to find but old-time feed stores will a have it. Seed it at about 3 to 4 lbs per 1000 square feet into well-worked soil. It is a large seed so try to get it about an inch deep.

Last but not least is garlic… the last edible crop we plant in the garden. Our goal is to have the garlic cloves root but not make too much top growth before winter sets in. This allows for a petty wide planting window. I shoot for Columbus Day in mid-October but planting until the end of October, or even a little later is not a problem. Get “seed” at a local farmers market selling locally grown stuff or order a variety grown in the Northeast US for best results. See this link for more details, page 27.

Jack Frost is coming but the gardening season continues.

Montauk Daisies, Nippon Daisy… Nipponanthemum nipponicum

Mother Nature saved some of her best work for the end of the growing season with the Nippon Daisy. Also commonly called the Montauk Daisy (because it is commonly found on eastern Long Island), its Latin name, Nipponanthemum nipponicum, makes it pretty clear that this plant is native to Japan (Nippon). Plant lovers may also know it by its former Latin binomial, Chrysanthemum nipponicum. By its current classification, it is the only member of its genus, one of 477 genera in the Aster Family. So much for the nomenclature.

Almost precisely one year ago, I was on a busman’s holiday in Rhode Island, looking over the Kathleen Mallon Memorial Demonstration Gardens on the campus of the University of Rhode Island. They are created and maintained by Master Gardeners in that state and named for an Extension Educator who was instrumental in launching the Master Gardener program there. I was knocked out by the brilliant white show of flowers from Nippon Daisy. My plant pal, Mary Jane, quickly identified it and told me that they were as common as clams in Rhode Island. Then I started noticing them everywhere in Costal New England.

Back home, the Nippon Daisy faded from memory until I was in a very good local garden center this summer and asked if they had ever heard of them. I don’t see them used much in SE PA. The plantsman at the garden center agreed but said he was beginning to get inquiries about it. Sure enough he had a few containerized plants and they are now lighting up my fall landscape.

Nippon Daisy is hardy in zones 6-9 and is a rugged plant. It tolerates dry sites, does best in full sun and makes its floral display late in the growing season. It will grow about three feet tall and wide and requires some simple/easy pruning for best performance. They can become “leggy”, that is, produces naked stems but with a bit of pruning the plant can be kept a bit more compact. Plan to cut them close to the ground each spring. Most landscape design advice is to plan for something that grows a bit lower in front of Nippon Daisy to hide its bare legs as the season progresses. Some references say deer don’t care much for it and it has stood up to a modest test in my landscape. The floral display beings in late summer and lasts late into the fall. White is the word. Maybe it is the contrast of white with the reds and golds of our fall foliage that makes it so attractive. Makes a good cut flower, too.

Reading about this plant, I learned that the famous plant breeder and legendary, pioneering geneticist, Luther Burbank hybridized this species with other closely related species to create Shasta Daisy and other popular cultivars which we still enjoy. Apparently, it was the brilliant white that made him choose Nippon Daisy for his work.

It seems that my revelation about Nippon Daisy would cause a chuckle among coastal gardeners but until I see more of them in Pennsylvania landscapes, I will continue to talk up this great plant.

It’s not too late to search for this fantastic daisy in local garden centers. Call it Montauk, Nippon or Nipponanthemum nipponicum, this plant is worth a look if you are in the market for an outstanding fall bloomer for a hot, dry site.

New Backyard Vegetable Publication from Penn State

Who said there is nothing new under the sun? Penn State just published a new, 58 page guide to backyard vegetable production titled Vegetable Gardening… Recommendations for Home Gardeners in Pennsylvania. It contains sections on mulches, container growing, irrigation and other cultural practices. Following this, there is a separate discussion of key plant groups: Brassicas (cabbages), root crops, bulb crops, leafy vegetables, tomato/eggplant and others.

There is information on seed starting, planting dates, spacing, pest management and harvesting…. everything beginning gardeners need to begin a successful garden. Seasoned gardeners are sure to pick up a few new ideas as well.

Dates described in the guide refer to central Pennsylvania. Those of us in the southern part of the state can adjust suggested dates about 10 days at both ends of the growing season. So, the gardening season is not over! Lettuces, turnips, radish are just a few of the tasty crops we can seed or transplant this month. With season extending rows covers we’ll be gardening until Thanksgiving.

Vegetable Gardening… Recommendations for Home Gardeners in Pennsylvania distills the knowledge of more than dozen Penn State experts and was organized by associate professor of Horticulture, Elsa Sanchez. You can order a copy or simply read it on line by going to this site.

Summer Color with Crapemyrtles

Most of the flowering trees and large shrubs we admire in the landscape are spring bloomers. Think dogwood, cherry, magnolia….crabapple, pear, serviceberry….redbud, lilac and viburnum.

So, stunning summer flowering trees are a treat for the eyes. One of the most conspicuous small trees/large shrubs that I see at this time of year is Crapemyrtle, Lagerstroemia. Common flower colors are shades of pink and red but white cultivars exist. In addition to the showy flowers, Crapemyrtle bark is very attractive…shades of cinnamon brown and gray that exfoliates with age. One respected plantsman says “If Crapemyrtle never produced flowers or leaves, it would not be a bad thing.” That’s high praise for bark characteristics.



One reason Crapemyrtle is somewhat unusual in Pennsylvania landscapes is its hardiness. Unless you are in zone 6 or 7 it won’t survive. Even in zone 6, expect dieback to the ground in severe winters. What has helped make Crapemyrtle more popular is a breeding program from the National Arboretum which added both winter hardiness and disease tolerance from Lagerstroemia fauriei to Lagerstroemia indica, resulting in about 20 wonderful hybrids. These cultivars, developed by Dr. Donald Egolf, all have Native American tribal names, so they are easy to spot. Tuscarora, Natchez, Hopi, Sioux, etc. A list of National Arboretum selections and a thorough description will guide you to good decisions.

Aside from being marginally hardy for parts of Pennsylvania, the plant is tough as nails. Yea, Japanese beetles like to chew on them and reference books describe other pests… but nothing life threatening. Crapemyrtles thrives in hot spots and tolerate poor soil. Full sun exposure is best.

So, if you have a hot spot in the landscape that can accommodate a multi-stemmed tree/shrub which will mature between 10 and 20 feet, and you would like a splash of bright color in the landscape in mid-summer, think Crapemyrtles. Start with the National Arboretum selections and beware of hardiness requirements. I counted more than 60 cultivars in my reference books, not all of them are appropriate for Southeastern Pennsylvania.

Growing Great Garlic

I won’t fake modesty here. I grew some great garlic. You can, too. It’s easy.

The garlic heads pictured here were harvested over the July 4th weekend… just a bit earlier than normal in this hot growing season.

I grow hard neck garlic, Allium sativum var. ophioscorodon, also known as ophio garlic, serpent garlic, top setting garlic, and echte Rokkenbolle or Schlangenknoblauch (to my German friends).

Hard necks produce a reproductive structure called a “scape”, a firm stalk ending in a swollen capsule which contains bulbils, not flowers. The scapes are quite tasty themselves, if harvested when they snap easily from the plant in mid spring.

Hard necks are different from the soft neck garlic you get in the grocery store. Hard necks have a shorter shelf life, fewer (but larger cloves) and for many people, have better, bolder flavor. As the name indicates, soft necks have no hard stem. They braid nicely. Most of what you see in the grocery store are softnecks, grown in China.

Oh, it gets even more complicated than this with different types of both hard neck and soft necks. And the names given to local selections of each type muddies the water even further. Recently, USDA researchers have concluded that there are actually many fewer garlic varieties than the common names would imply. Local adaptations and response to environment account for the perceived differences. For a great read on garlic, consider the text, Growing Great Garlic by Ron Engeland. It sorts out a lot of the terminology, history and origins of this unique food and provides excellent advice on growing all types of garlic. Penn State’s Growing Bulb Crops publication also has enough info to get you started.


Back to the basics. So, if harvest time is about the 4th of July, when is planting time? Columbus Day…more or less. That’s a good general guide for planting garlic in Pennsylvania. You simply stick a clove, (root end down) an inch or two deep into well prepared, rich garden ground, spaced about every 7 inches. It often makes sense to make a bed and plant three rows together, about 10 inches away from adjacent rows. Cloves will root well and make a few leaves before the soil freezes up. Then mulch with straw or leaves and wait for them poke thru in the spring. Keep the planting weed free. A shot of rich compost or fertilizer in early spring is a good idea.

That’s about it. Garlic has few pest problems besides weeds. A few hand weedings, as the mulch deteriorates, is necessary. When to harvest is an important consideration. Too early and clove size and maturity is reduced. Too late and cloves separate within the head and quality and shelf live diminish. I have followed Engeland’s advice and harvest my Ophios when 40 % of the lower leaves have died, leaving about 6 green leaves at the top of the plant at the time of harvest. Your goal it to have well segmented cloves that have not begun to separate within the head. This is usually about mid-July for the varieties I grow.

Post harvest care is important. I move my harvested garlic immediately to a shaded, well ventilated area to “cure”. Although many folks seem inclined to let it lay out in the hot sun, this is not the best approach. Since most of it is consumed by Christmas, no special storage is required. Most references say to store garlic at 55-65 degrees F and 50 % humidity. So a cool cellar, or similar space, will work very well.

Note that you’ll likely be saving some of you own crop as “seed”. Not literally. You’ll save some heads that will be broken into separate cloves for planting in October. So if you happen to harvest some over mature heads, they make good planting stock. Or, just eat them first.

Of course you have to get started somehow. Where do you get planting stock? Your best bet may be a local farmers market that is selling their own, farm grown garlic. This will obviously be well adapted to your area. If this doesn’t work, the internet is full of sellers in the Northeast US. Don’t plant store bought garlic. It is unlikely to be well adapted to our growing conditions.
I still have a lot to learn about garlic. I’d like to try some soft necks. Add a few more hard necks. But the important things I have learned are that hard neck garlic is easy to grow, it’s better tasting than store bought and it keeps well until Christmas (and beyond). Give it a try this fall.

Getting Dry... Good, Bad and Ugly

OK getting dry might be an understatement. It is DRY in Bucks County, PA. When I see roadside weeds wilting, it’s dry. And today’s newspaper says, “Hot and dry with no rain in sight”. I think that means no rain in the forecast. Sure enough, the 7 day forecast is bone dry.

Let’s start with the good aspects of dry. My farm friends (who have irrigation) tell me that they will take a dry year over a wet one anytime. It is possible to add water but impossible to take it away. Heat and sunshine combined with timely irrigation equals wonderful tomatoes, peaches and other produce. Sure they have the chore of moving pipes and running pumps but they have control of the water. Same thing goes for home gardens.

And that late blight problem we are watching… it's gonna have trouble getting cranked up in these conditions. Notice how the sycamores have leafed out again after the ravages of early season leaf diseases. Thank the dry heat.

The bad…I think most folks underestimate the damage water stress causes to plants. Especially woody plants. It’s pretty obvious when you neglect to water the petunias or tomatoes. They wilt and probably recover when watered; if not, they die and you move on. In any event, they are annuals so you get another chance at minimal expense. With woody plants, the effects of drought are often harder to see and the effects may take awhile to manifest themselves. Often times it is borers, or even disease, that finish off these drought stressed plants. It may take years.

Just for fun, I observe lots of new landscape plantings. New housing developments, commercial sites, even the grounds of our Extension office. Frequently (if not usually) the newly established trees and shrubs are subject to severe drought stress in the first 12 months of planting. When they can least tolerate it. It is good to recall that these plants arrive to the site with a severely diminished root system. A lot of it was left behind in the nursery when the plant was dug. Even containerized plants have an abnormally restricted root system. Believe it or not, sometimes the plants that are established on these job sites arrive already drought stressed. Dormant plants that don’t “ leaf out” normally are suspect in my eyes.

OK. What does this mean? Right now, trees and shrubs that were planted within the last 12 months need water. If you wait until leaves wilt and fall off you have waited too long. Anticipate the watering needs of these plants and give them a good soaking before they wilt. Check back in a week and repeat if necessary. A good soaking is hard to quantify. How about this… 5 – 10 gallons per tree, applied at the base of the plant, slowly so that it soaks into the ground. Repeat weekly as needed. This requires a hose and some time. A watering can won’t cut it. Mother Nature will eventually come to our aid but until them, make a date with your trees and shrubs weekly. That green thing shown above is a "gator"; an irrigator bag. A handy device that allows the bag to drip water into the soil at a nice, slow rate, but you can fill it quickly.

The ugly…of course, complete neglect in a drought results in dead plants. Maybe not dead now but drought stress can show up as “winter injury’, borer damage or even disease in the long run. Going on vacation? How about a good soaking before you head off. The trees, not you.

Finally, although it is hard to imagine in a drought, it is possible to have too much soil moisture. You can over water. Automatic irrigation systems (improperly manage) kill plants.

Wouldn't it be wonderful if it rained an inch a week, every week, preferably between midnight and dawn. There are places in the world where temperatures and rainfall regular and predictable, within the growing season. Pennsylvania isn't one of them.

Late Blight Rears Its Ugly Head Again

Late blight, the disease that wrecked many gardeners’ dreams of a fresh tomato sandwich last year, has been found, wide-spread, in western Pennsylvania. Many horticulturists, me included, were optimistic that we would be spared in 2010 but that hope now appears to be dashed. At this time, late blight has only been confirmed in three western PA counties but all Pennsylvania tomato and potato growers need to be vigilant. For a good discussion of the disease including images, see this site; or this site
To recap…. Late blight is a devastating fungus-like disease of both tomato and potato. Symptoms include rapid blighting of foliage and fruit. Tomato stems exhibit chocolate brown lesions. Leaves have blotchy brown spots and may produce fuzzy, whitish masses on the underside of leaves, especially in the morning when dew is present. Note that this is very different from early blight which results in yellow-brown lesions on lower leaves, containing concentric rings of dead tissue.

What’s a gardener to do? First, be vigilant. Inspect tomatoes and potatoes daily for late blight symptoms. Penn State will be tracking the disease in an attempt to alert commercial growers about the threat of late blight in their vicinity. It’s one thing to miss out on a tomato sandwich…quite another thing to lose a big chunk of your income. Farmers have a lot at stake with a crop of tomatoes or potatoes. Contact your extension office if you think you see late blight. Feel free to bring samples to the office for confirmation of the disease.

How about protecting those plants? Conventional gardeners and farmers can use products containing chlorothalonil, for starters. New foliage needs to be protected as it grows. Organic gardeners have copper fungicides, which will not provide the same level of protection as chlorothalonil but are better than nothing. If you plan to let Mother Nature take its course, and do nothing, at least be prepared to destroy infected plants at the first sign of disease… your neighbors will thank you. Best bet in small gardens is to bag the plants in plastic and cook them in the sun.

Any chance we’ll escape late blight in eastern PA? I was an optimist in the winter because it is known that the organism does not survive without living tissue in the North and Old Man Winter took care of that (except for potato cull piles) . But now that the cat is out of the bag…. I think we’re in for another year of greasy, black fruit in the tomato patch.

Dang… I was feeling good; tying up plants in the rain yesterday. Now I wonder if those raindrops were accompanied by late blight spores. Current conditions are ideal for late blight infection.

Beautiful Gardens... Near and Far

In the past month, I have visited two of the best public gardens in the world….one in our backyard, Longwood… the other across the Atlantic, Keukenhof. Lucky me.

I was in the Netherlands visiting family in early May and it was tulip time at Keukenhof. Perfect timing. Keukenhof is a 76 acre garden that features spring flowering bulbs. Supported by the bulb industry, their website says it is the most photographed place in the world. I can believe it. Every step through the garden compels you to snap another picture. With all due respect to Longwood, it is the best public garden I have ever seen. There are more than 7 million hand planted bulbs on display. Four million tulips, not to mention the daffodils and grape hyacinth… 20, 000 lilies.




Wow. If you ever find yourself in Europe in April, don’t miss it.

Back at work… Penn State President Graham Spanier conducts a very nice program for new and newly tenured faculty at Penn State called the Roads Scholars Tour. About 50 faculty witness Penn State’s presence and impact across Pennsylvania. They visit Commonwealth Campuses (there are 19 of them across the state), Hershey Medical School and other places where Penn State has had an impact. This brings us to Longwood Gardens. There are lots of Penn State graduates on the staff here and I learned about many cooperative research ventures involving Penn State and Longwood. My pal Dr. Casey Sclar, Plant Health Care Division Leader at Longwood led the Roads Scholars and President Spanier on a great tour of this world class garden. Casey said Longwood was about to present the largest lily collection in the world. I guess there will be more than the 20,000 at Keukenhof. Yikes!





Unlike Keukenhof, Longwood is open 365 days a year. What a challenge for the horticulturists there. If you have not visited lately, put it on your “to do” list.

Tomato Time

Ask most vegetable gardeners what single thing they would not live without in their garden and it is probably the tomato. Makes sense, tomatoes are easy to grow and reliably produce lots of fruit; they are tasty, good for you and bear from July till frost. There is a huge selection of varieties to choose from so tomato growers don’t get bored. And it is just plain satisfying to pick a big, fat, ripe tomato and fix yourself that first sandwich or salad.

Growing tomatoes is so easy I hesitate to offer advice but here goes. Even veteran tomato growers got a surprise last year with late blight and I’ll offer a few thought s on this disease. Here’s a link to Penn State’s tomato growing guide. See page 55.  It contains lots of good detail on tomato culture…and its relative, the eggplant.

Grow your own transplants or rely on the local greenhouse? That is a big question. Certainly growing your own plants gives you more control over what varieties you’ll enjoy. But many of us just don’t have the time, growing conditions or skill to produce a good transplant. I find that small, local greenhouses offer the best chance at getting an excellent quality plant as well as decent variety selection. Try your local farm market, too. Sometimes farmers start more transplants than they need and sell the rest.

Tomatoes are heat loving plants. They will not tolerate a frost so we wait until mid-May in Bucks County to plant them out, unless you have some device that will protect them or are willing to gamble that Mother Nature is looking out for you. By Mother’s Day, we are almost always past danger of a hard freeze, so that’s a good tomato planting guideline. Makes sense to look at that 10 day outlook and adjust as necessary. You can plant out earlier using low tunnels, wall-of-water, row covers and other heat retention devices if you are the kind of person who wants that first tomato on the block.

Varieties… the list is endless. Entire websites are devoted to tomato seeds and varieties. Here are a few suggestions based on Penn State evaluations, personal experience and high praise from knowledgeable tomato people.
Brandyboy… an improved Brandywine type will give you excellent size and flavor without the downsides of straight Brandywine that heirloom folks praise. Fabulous…is just that, a fabulous, tasty slicer that will not disappoint you. Celebrity is an early fruiting, smaller but reliably good slicer. Mortgage Lifter is a good choice if you are in the heirloom market; and how can we overlook a variety called Bucks County from Burpee.

Plant breeders have been taking the best qualities of heirloom types and combining them with traits that improve yield uniformity and disease resistance. I’m not talking about those hard, red cardboard tasting things you find in the mega-mart. Plant a Brandywine and a Brandyboy side by side and judge for yourself. Space is limited so I’ll leave it to you to explore the plum, cherry, grape Roma and other small types but I will drop a name…Mountain Magic is reported to be a superb new “salad” size tomato that will be available in limited quality this year. In addition to yield and flavor it is resistant to late blight.

Ah late blight… the tomato/potato disease that took a lot of the fun out of last year’s garden. You may recall tomatoes turning a greasy, black color and croaking about mid July. For a more detailed discussion of the disease, check out previous blog entries.

Bottom line… no reason to expect late blight to be the scourge it was in 2009 but keep your eyes open and let us know if you see it. Gardening-wise, there are no special gardening practices that you can employ to prevent late blight. No need to sterilize soil, tools tec. Rotating planting location is always a good practice but will have no effect on late blight.

More likely, our old nemesis, early blight and Septoria leaf blight, will be infecting plants. Neither are the devastating fruit rotter and plant killer that late blight is but they overwinter her very well. Stake or cage plants to encourage quick drying and you’ll see less of these diseases. Inspect plants when you purchase and bypass those with spotted or yellowing leaves.

A final thought… consider planting through black plastic mulch. It is amazing what it does for soil heat and water retention, weed control and overall soil physical prosperities.

Pretty Spring Flowers

What a fantastic floral display Mother Nature puts on in Spring! And to think that some people would call her brush strokes weeds.

Right now, yellow rocket Barbarea vulgaris, is in full bloom. This plant is classified as a winter annual. This class of weeds germinates in the fall, survive the winter in a vegetative state and then bloom and set seed in the spring… fading away as the days lengthen and the heat of summer approaches. They produce a nice crop of seeds which will lay dormant until fall when the whole annual cycle begins again. Isn't Nature cool?

Of course this plant can be a weed if it is growing in competition with garden or crop plants. In fact there is a good chance that your garden is full of winter annual weeds right now. Many of the Brassica family (also called crucifers or mustards) are winter annuals. The family includes Virginia pepperweed, Wild mustard, Shepherd’s-purse, Bittercress, and Field pennycress. They are closely related to cultivated plants such as broccoli, cabbage and Brussels sprouts.

Other winter annuals include Common chickweed, Purple deadnettle and Henbit. Purple deadnettle, shown here, is lovely but I am more partial to Henbit's scalloped leaf margins and daintier flowers.

In addition to being pretty, many winter annuals provide forage for bees. They cover the soil and prevent soil erosion. Some call them the poor man’s cover crop.

So enjoy the pretty spring flowers produced by winter annuals. They won’t be here long. Instead, the flip side of annual weed life cycles is beginning. The summer annuals...crabgrass, pigweed, foxtails and ragweed are just getting started. It’s a little harder for me to warm up to these plants. And they are more likely to occupy your time in the garden than the winter annuals.

Want a good weed/wild flower book? Weeds of the Northeast is a great picture book containing more than 280 species common to the northeast U.S. It was written by the excellent folks at Cornell University, a sister “land grant institution” to Penn State.

The National Pastime… Baseball and Lawns

Your lovely lawn and baseball…. what’s the connection? I am not talking about the days you spent as a kid tossing the ball around. Nope, I am talking about crabgrass and grubs and dandelions.

Marketing experts have probably figured something out…. Guys take care of the lawn and guys listen to baseball on the radio. So it is not surprising to hear lawn care advice when these two come together. For the past three weeks I have been advised to apply crabgrass control or meet certain disaster from the claws of crabgrass. I guess I can’t blame the marketers… their crabgrass control timing is in the ballpark. A bit early, but with crabgrass control it is better to be early than late. Factor in the procrastination factor and other manly distractions and I understand the marketing strategy.

Crabgrass is an annual grass that germinates when soil warms to a critical temperature. The date varies from year to year but in Southeastern PA but is reliably after the team comes north for opening day. Sometimes weeks after. But to be on the safe side, and since most of the preemerge products will not control crabgrass after it has emerged and all of the products require Mother Nature to water them in... getting the job done before you get a look a the fifth starting pitcher is a good idea. If crabgrass applications begin to conflict with the federal tax deadline you are skating on thin ice.

Before we tackle the crabgrass herbicide options though, let’s step back and ask a question. Got crabgrass? If you have not observed crabgrass in your lawn for the last several years and your lawn is reasonably dense, shift you attention to the bull pen problems or the backup catcher instead. Not every lawn needs preemerge crabgrass control every year. Putting your efforts into growing dense turf and raising the mowing height can eliminate the potential crabgrass problem. Get a Penn State soil test and follow the recommendations. Kick the deck up a notch. Lime, fertilizer and proper mowing height are the basis of lawn weed management.

OK, assuming you require crabgrass control, what are your options? This publication describes pre-emergence herbicides that will do the job. There are many options including one (dithiopyr) for major league procrastinators! You can apply this one before or after crabgrass germination and still get excellent control. Most of these products are sold as an additive to fertilizer. Or you can hire a lawn care company to do the job for you.

Next up… grub control. Another manly endeavor brought to you by salesmen who know their audience. I’ll try to talk you out of that another time.

Berries in Winter !!!

Winterberry … what a great name for this deciduous holly that is in all its glory after a winter snow storm. Its official common name is Common Winterberry. Its Latin name is Ilex verticillata and plant people will recognize that Ilex is the same genus as the other hollies, most of which, are evergreen.

Winterberry holly drops its leaves in the fall. And that is what makes it such a show-off in the dormant season. Add a background of drifted, white snow and you have a spectacular landscape plant. It’s not surprising that cultivar names include Stoplight, Wildfire, Red Sprite and Sparkleberry. Depending on the cultivar, they will grow to a height of 5 to 12 feet.

This plant has several qualities that make it a good choice for Pennsylvania landscapes. It has very few pest problems….I’ve never seen a splotch or a notch from disease or insect damage. It thrives in wet sites, which broadens its potential as a landscape plant. And then there is the fruit. Many plants produce interesting fruit but the combination of the brilliant, red color and the lack of competition or camouflage makes Winterberry holly fruit really special. And it hangs in there until late winter, long after most fruit has dropped or been eaten by birds.

Like the other hollies, winterberry has male and female plants. Bet you never thought of that. Most plants are hermaphrodites… male and female parts on the same plant or even in the same flower. Hollies are like us…separate sexes. This means that you will need to plant a male holly along with the showy, fruit-bearing females so that pollination, and fruit set occurs. Your nursery or garden center will help you select the right male. You can tuck him nearby and Mother Nature and the bees will do the rest.

There are many cultivars of Winterberry holly to choose from. Longwood Gardens and the Scott Arboretum have excellent collections. There are even yellow fruiting forms. Some are hybrids of Ilex verticillata and Ilex serrata, Japanese Winterberry.

Longwood Gardens researchers recently evaluated winterberry holly cultivars. Check out the results in a two part (part 1) (part 2)wrtite-up in American Nurseryman Magazine The National Arboretum has great info, too.

Late Blight - 2010

Ok. First, the take home message…. Tomatoes growers should not expect the 2009 epidemic of Late Blight to return in 2010. And… the disease organism that causes late blight has not survived in soil, pots, stakes or other non-living tissue in Pennsylvania. So, chill out on all of those elaborate plans to sanitize the garden. If Late Blight interests you, read on. If you grew potatoes last year, and have any left over, be sure to read to the end of this blog because you could cause a problem.

Last week I spent an entire day, in one room….learning about tomato production at the Mid-Atlantic Fruit and Vegetable Growers Conference in Hershey, PA. I was in charge of making sure the projector worked and the lighting was conducive to learning, otherwise I would have slipped out to catch that session on horseradish, among others, down the hall.

A lot of time in the tomato marathon was devoted to late blight, the disease that caused widespread destruction of tomatoes in the Northeast US last summer. Two things were responsible for that epidemic. One… infected transplants were sold throughout the Northeast thru the “Big Box" stores. The stores were supplied by a large greenhouse business that had late blight (a disease caused by a fungus-like organism) in their production system. I am sure that neither the stores nor the greenhouse business intended to create such an epidemic. But the end result was distribution of infected plants over the Northeast... a devilishly effective Step One: spread a very contagious organism over a wide geographic area. Late Blight spreads by spores which can blow 30-40 miles in moist air. It can infect tomato and potato as well as some weeds in the tomato family (and petunia, I learned).

Thanks to an eagle-eyed plant pathologist from Cornell, the problem was diagnosed every early. He blew a whistle and everyone paid attention, otherwise, it could have been worse. He said it may have been the most constructive thing he has done in his long career.

Step Two was Mother Nature. She picked 2009 to provide excess moisture and cooler than normal temperatures from June until September. Perfect for the Late Blight organism. Hey, whose side are you on Ma, the tomatoes or some pathogen? I guess we know now. Seems she loves all of Her creations, including Late Blight. Hmmm.

The good news is that the organism that causes Late Blight has no history of overwintering in the Northeast U.S. Once infected plants die, so does the disease. Plant pathologists are concerned about a situation in which late blight does develop the capacity to overwinter here, but so far that has not occurred (as far as they know).

So again, the really good news is that both gardeners and farmers have no reason to expect late blight to be any more of a threat in 2010 than it was in any other year. And 2009 can be considered an unusual year for the disease. Since the organism requiures a living host, there is no need to plan elaborate crop rotations or go to extremes in trying to kill what is already dead. Dead tomatoes equal dead late blight. Unless the spuds get us….

Now about those potatoes…. Recall that late blight can survive in living tissue and since the same organism infects both tomatoes and potatoes … do you know where your spuds are? The concern is that infected potatoes are laying cull piles or worse, stockpiled for planting. Don’t do this! Buy certified, clean, potato planting stock!. It ain’t worth starting the epidemic of 2010 to save a few bucks on seed potatoes. And that means your precious heirloom varieties, too. If you grew potatoes in 2009 and experienced late blight, be alert for volunteer spuds next spring and destroy them.

No problem with saved tomato seed.

I located an excellent summary of late blight and its management at UMass extension. It provides and excellent overview and advice for gardeners, including those using the organic approach.

For a utube segment by PSU's own plant pathologist, Beth Gugino, see this.

Bring me... A Shrubbery!

According to Wikipedia “A shrubbery is a wide border to a garden where shrubs are thickly planted; or a similar, larger area with a path winding through it… a collection of hardy shrubs … distinct from the flower garden.” Wikipedia also referenced the poet Milton and more to my taste, Monty Python. You may recall that The Knights who say Ni demanded a shrubbery of King Arthur. A nice one but not too expensive.

Penn State’s new Guide for Selecting Shrubs for Pennsylvania Landscapes says .. “Shrubs act as intermediate units working in partnership with trees to provide scale and structure for the larger shade trees and the people and animals that interact with the landscape.” Yes indeed , my cat sleeps in the shrubbery.

This is a great new reference created by Penn State Horticulture Department faculty. It describes more than 200 shrubs for Pennsylvania landscapes. For planning purposes the guide is divided between deciduous and evergreen shrubs. These are arranged by size…less than 3 feet, 3-5 feet, 5-9 feet, etc. Excellent information for planning a shrubbery.

Shrubs native to Pennsylvania are indicated for those of you who are planning with this in mind. Last year I planted Clethera and Itea, a couple of natives that tolerate very wet sites. Great plants. Bees love them.

With more than 200 species mentioned, you’ll of course find Junipers and Viburnum, Taxus and Rhododendron, Cotoneaster and Cornus. But also less know genera such as Xanthorhiza, Indigofera, and Eubotrys.

It won’t be long before we can think about planting outside again. A Guide for Selecting Shrubs for Pennsylvania Landscapes is a great planning reference and inspiration. Read it on line, call us (215-345-3283) for a free copy or order from Penn State.