Sunday, September 21, 2014
Entrance to the Mary Livingston Ripley Garden on the National Mall
[Second in a series on Smithsonian Gardens; introduction here, and part 1 here]
The Mary Livingston Ripley Garden, tucked into a narrow space between two Smithsonian museums, the Arts and Industries Building (closed for renovations since 2006) and the Hirshhorn Museum, is one of the Smithsonian's smallest but it's one of my favorite gardens in Washington, DC. Like the Butterfly Habitat Garden, this oasis just off the National Mall is easy to miss, and tourists focused on the memorials, monuments, and museums will walk right by it without ever knowing it's there.
Monday, September 15, 2014
Bit by bit, the garden is recovering from a brutal winter. It may not look like much from above: there are a couple of empty spaces where palms used to grow, the hardy banana (Musa basjoo) hasn't grown nearly as big as it did last year (see Everybody loves my big banana), and the figs were killed to the ground and are coming back from the roots, but hidden underneath all that foliage are some plants that are just now hitting their peak.
View of the garden from our roof deck
Thursday, September 11, 2014
Passiflora caerulea, a beautiful monster
There are some plants that, beautiful though they may be, you should be wary of inviting into your garden. These are plants that grow so fast, so big, and propagate themselves with such enthusiasm, that they will bully and overwhelm anything the least bit slow or small or dainty until one day in mid to late summer, you realize that several of your most precious plants are missing.
Monday, September 8, 2014
I haven't been blogging because I've been visiting with my family in Buffalo for the last week. Now that I'm finally home I have a lot of things to catch up on, so for now I'll just show some of the sunset photos I took from the plane window as I was flying into Washington, DC this evening. Please click on the photos to see them full size in my Flickr album!
Thursday, September 4, 2014
Phytolacca americana L.!
You are reviled in the online gardening discussions,
Weedy, invasive, hard to control
But if you're a weed, you're just doing what weeds do:
Growing where you can, when you can, conspiring with the birds to spread
And like your friends the catbirds and mockingbirds you were here first
(Along with poison ivy, virginia creeper, so many other "weeds")
You even predate the honeybees on your flowers (they came with us!)
So who are we to say you don't belong?
This land is your land, it always was:
Even Linnaeus recognized that you are as americana as we are, if not more.
As for me...
You take me back to when I was just a kid (albeit an odd child)
Using the beautiful magenta juice from your berries as ink
And when other teenagers were experimenting with marijuana
I was experimenting with a "weed" of another kind,
One that grew taller than me, huge leaves hinting at the tropics
But with tender spring shoots;
(My mother never knew if these things were going to kill me--
the shaggy mane mushrooms made her especially nervous,
although they were among the few mushrooms I could confidently identify--
but pokeweed, you're certainly poisonous if not prepared properly,
or so they say, I never tried boiling you only once; I wasn't that adventurous)
And with a bit of butter you were delicious.
[After writing this, I came across this very nice blog post on the same subject at Nadia's Backyard: Pokeweed, American (Phytolacca americana): The Jekyll and Hyde Plant]
Saturday, August 30, 2014
Scottish Rite Temple, October 2012
In early February, when we were in the middle of our coldest winter in a very long time, I wrote a blog post rounding up several windmill palms (Trachycarpus fortunei) that I've encountered in the city. Most of these palms were several years old and had suffered little damage from our recent mild winters but as I wrote in February, "...our coldest winter in 20 years will surely put these palms to the test. A general rule of thumb is that single digit temperatures are likely to cause damage, and temperatures below zero will cause massive damage and in many cases kill the palm outright (although duration of the cold is also critical). This makes windmill palms marginal in zone 7: sooner or later, they will experience temperatures capable of killing them."
Thursday, August 28, 2014
Yellowing leaves: an early sign of Basil Downy Mildew
I just harvested what will probably be my last batch of basil (Ocimum basilicum), for what will probably be my last batch of pesto this year. This is depressing for several reasons. First, I love basil and I love pesto, and I always find the end of the basil season a bit depressing. Second, my basil usually lasts much longer, only petering out in October once nights start turning consistently chilly. But most of all, I'm depressed because I discovered that my basil has Basil Downy Mildew, a new disease that I've never encountered before, and that promises to be a major problem for basil growers--and lovers--in the next few years.
Leaf discoloration from Basil Downy Mildew
One thing I love about basil is how fast it grows, and how productive even two or three plants can be. I grow my basil in a container on my back deck, where it gets the heat and sun it loves all day long. I never start it from seed, always buying plants from a local garden center or farmer's market, and this year started like any other. The first sign that something was wrong came just a couple of weeks ago, when I noticed yellowing older leaves on my basil. But it was still vigorous and growing strongly, was yielding well, and I thought maybe I had stressed it by over- or under-watering it. Consistent watering is not my strong suit! But the yellowing progressed, the older leaves developed brown lesions and started dropping off, and younger and younger leaves were affected. When I harvested the basil I noticed a dark fuzzy discoloration on the leaf undersides, which I assumed was some kind of mildew. I still wasn't terribly concerned; I've had mildew on various garden plants, and this seems to be an especially bad year for powdery mildew on several plants that are prone to mildew anyway: peonies, columbine, and Verbena bonariensis. I've never seen mildew on basil before, but I chalked it up to the summer being a bit cooler than usual, because basil certainly loves heat.
Leaves infected with Basil Downy Mildew, bottom (left) and top (right)
But the disease progressed rapidly so I did some Googling and that's when I started to get a bit alarmed. I sent photos to Margaret McGrath, a plant disease researcher at Cornell University, who confirmed that my plants had Basil Downy Mildew (BDM). BDM is a new disease, reported in Europe in 2001 and found in the United States for the first time in Florida in 2007 but already reported from all over the country, even Hawaii. The disease spreads quickly and easily, progresses rapidly, and can wipe out a grower's entire crop of basil in a matter of weeks. Even in its early stages the plant's foliage is disfigured and ruined for commercial use. I'm lucky this is the first time I've encountered it, but this isn't likely to be the last. No basil cultivars are (yet) known to be resistant, so I suppose that gives the plant breeders one more thing to keep them busy!
Underside of leaf infected with Basil Downy Mildew
Basil downy mildew can be controlled with fungicides, but I don't use pesticides of any kind in my garden so for now I'm at a bit of a loss and don't have any tips for control. The best advice is probably to monitor plants closely and immediately remove and destroy any that show even a hint of disease. The good news is that the mildew isn't toxic to humans, although it can and will kill your basil. More good news is that the disease probably (probably) won't survive cold winters; but it can spread by infected seeds so if you have BDM-free plants it might be wise to save your own seeds and grow your own!
Please share this post to help get the word out about this destructive new disease! Dr. McGrath and her colleagues are gathering reports of Basil Downy Mildew so if you have it, you can report it here: Basil Downy Mildew Monitoring Program (this link also has information on submitting samples). Has anybody else in the Washington, DC region encountered this disease?
For more info:
Expect and prepare for downy mildew in basil (Margaret Tuttle McGrath, Cornell University)
Downy mildew on basil (photos, Cornell University)
Basil Downy Mildew and the Ornamental Greenhouse (A.R. Chase, GPN)
Fungus threatens basil plants for this year and beyond (Adrian Higgins, Washington Post)
Downy mildew on basil (Nancy F. Gregory, University of Delaware)
Basil downy mildew (University of Maryland Extension)
2014 Basil Downy Mildew Outbreak Our Worst One Yet (Debbie Roos, NC Cooperative Extension)