First, that weird name, Lead Plant. Says the Missouri Botanic Garden, the plant was once thought an indicator of lead in the soil. Meaning what? Lead to mine? Or lead contamination, land to avoid? Doesn't say, dunno. As usual, Latin is better. Amorpha canescens. Amorpha means mis-shaped, in that the flowers are missing most of the petals their other pea-family relatives have. Just one here, thank you. Canescens means grey or hairy, which the delicate ferny foliage certainly is.
The plant is as tough it is adaptable, native from the Canadian sub-Arctic to the Gulf Coast. At home, it's a small-scale early-Summer thrill to puzzle experts as well as just-folks gardeners.
The profuse spikes of indigo-blue flowers are way too early to be caryopteris, which is the same size bush (a foot or two high and two or three feet wide) but doesn't bloom until August. But caryopteris foliage is simpler and a bit bigger anyway. As are the leaves of buddleia, the other possible floral look-alike. But it too is in bloom much later in the season, not by the end of June, and even in the dwarf forms is distinctly bigger and more erect.
All Lead Plant wants is these three things:
1. Lots of sun.
2. Good drainage in the Winter. 3. Freedom from herbivores, deer included: The foliage tastes great (to them) and is nutritious too. No idea of its lead content though. And all you need to do for your Lead Plant is to cut it to the ground without mercy in early Spring: As with caryopteris and buddleia, the flowers happen at the tips of new growth, so last year's isn't worth a damn.

I haven't been face-to-face with actual marijuana for, oh, 40 years. Tried it, didn't like it. So I was very slow on the draw in realizing that one of my vitex bushes is doing a serious pot imitation.
Here's the bush, putting out its lush eager Spring growth.
A foliage close-up. Look familiar?
And here's a shot of an actual marijuana. (Thank you, Google.)

They are amazingly similar, but pot has more leaflets than vitex. Seven instead of five. And pot leaves are two or three times as big.
But with pot, as with vitex, the puff I mean the proof is in the pudding. When the vitex blooms it gets narrow spikes of tiny lavender-blue flowers, not the odiferous buff-colored clumpy things of marijuana. OK, blue-ish with today's pot-imitating species, Vitex incisa. Perhaps this is the reason that if you only have one vitex, plant what everyone else plants, Vitex heterophylla. Here's one of those in bloom out in Wellfleet. Now that's colorful!
But you know me: If I have one of something, well why not have all of its cousins? So I grow Vitex incisa too. That's one of my, ahem, hardy passion vines, 'Incense', crawling through the vitex, and adding one of its flowers to the picture.
'Incense' is far and away the easiest of the passifloras to establish, and the flowers are are the biggest too.
Incredible. Sun in the Summer, good drainage in the Winter, and you should be able to get some 'Incense' in your garden almost anywhere in Zone 6.
A nice druggy coincidence there. The name if this variety, planted so near my inadvertently pot-like Vitex, really is 'Incense'. Just as incense tried to do with pot in real life (I'm told), this 'Incense' is trying to cover up this "pot." Even better: 'Incense' was developed by the US Government, who was trying to create a hardy passion vine with an agricultural fruit crop. But instead—you can just hear those dweeby DOA guys saying "darn!—all they got was a hardy passion vine with incredible four-inch blue flowers. That still doesn't explain why they named it 'Incense', though. Maybe they were smoking something that day? A thought.

I always thought that this delicate-looking, densely-growing, gold-leaved hedging plant wasn't hardy in New England, but then I saw it at a friend's garden in Stonington, even farther away from the mild ocean influences then I am.  Yes, it gets a bit of dieback each Winter, but it bounces right back in Spring. And she doesn't protect it at all either.


So, OK. I'm trying it in my sheltered Zone 7 Wannabe garden on the South of the house. Tall hedges to the East and West and South muffle the Winter wind, and the South exposure captures the height of the Summer sun and heat.  And one of my more tender Southern magnolias—Edith Bogue—is already thriving here.

So if I'm going to have this delicate Zone 7 beauty here in Hopkinton, the South Garden is the spot.


Hooray: The Stonington owner just gave me a branch that had rooted out in the soil all on its own. So it's in, and the experiment—Is it hardy here too, not just 8 miles West?—has begun.

Butterfly bushes usually bloom in Summer, at the tips of the new stems they started that Spring. So last year's growth isn't useful at all: After growth starts in the Spring, cut each limb back to the lowest possible pair of new leaves. If you're not horrified over how drastically you've pruned, keep going.
There's a butterfly bush that blooms in Spring too, and so whatever you do for your Summer-blooming butterflies, do the reverse for this one.
It blooms on last year's wood, so don't do any pruning until the bloom is well underway, or even finished. And while Summer butterflies often get huge amounts of Winter die-back, Spring butterflies are so hardy that their wood lives year after year, and they can get bigger and bigger: As big as a lilac, and usually much wider.
But since my philosophy is "Why let anything grow naturally if I could be torturing it instead?", I'm getting out the pruners to take full advantage of my Spring butterfly's oddball talents.
The wood is hardy year-to-year? Fine: Then I'll pick one main branch, stake it up, cut off the lower limbs, and—voila—I've got a small tree, a "standard" as we say.  A "standard" as anything that's trained into a ball-on-a-stick form that wouldn't otherwise grow that way.
The younger branches tend to weep, especially as they bloom? Great! I'll get the trunk high enough so that I can have a (small) weeping tree.
And the bush comes in a form with conspicuously silver leaves, not just the regular fuzzy green ones? That's the one for me.
Here's the progress, then, on my silver-leaved, weeping, standard of Spring-blooming butterfly bush.
I've staked up a center branch to grow as a trunk, but then, in the way of much in any garden, got involved with a million other things for a couple of years. Time to prune and primp and reveal what's what.
How 'bout those lavender blooms in three-foot-long spikes? Every garden needs more fireworks.
With the stray lower branches pruned off, the young standard's trunk and head-growth are showing nicely.
And as the plant ages, the number of branches in the canopy increases nicely, making a fuller, wider, and lower-weeping canopy. That's a deep-purple ninebark bush at the left-front, cut to the ground each Spring. It will get six feet tall by September, which is just how tall I should get the butterfly's trunk so the weeping silver branches will mix nicely with the purple of the ninebark.
That's a blue-leaved rose at the back, which will get big enough to form a darker background to the whole ensemble.
Give me three more years, and this will be stunning.
PS: OK, time to grow up and switch over to the Latin:
Silver-leaved Spring-blooming butterfly bush: Buddleia alternifolia 'Argentea'
Purple-leaved ninebark: Physocarpus opulifolius 'Seward'
Blue-leaved rose: Rosa glauca

One hallmark of plant passion is the hunger for the new—or put another way, the openness to an ever-larger world. Yes, we love what we know, the breadth and depth of it, but at the same time we are eager for the new. It's not a zero-sum game: loving something new doesn't necessarily mean we stop loving something old.
And of course, newness itself is something to love. We love a plant (in part) just because we haven't grown it before. It's desirability after we've been together a year or two? A question indeed.
Sophora davidii in this category for me. I hadn't even heard of it until a couple of years ago. Sophoras—and there aren't many sophoras to start with—are trees, and yet Sophora davidii is a shrub. With comparatively tiny leaves, and a heavy Spring bloom of thousands of small white honeysuckle-like flowers with a just-subtle-enough-to-escape-the-notice-of-the-non-serious-gardeners lavender-blue blush on the outside. A dense habit, and plenty of thorns. Very drought tolerant, very hardy, and in those respects at least, like a cousin of a hardy quince.
Mine is still small enough to keep in a pot until I figure out just where it must be planted.
Meanwhile, here's the much larger, but still adolescent, shrub at Wave Hill, already in full bloom because the climate is a week or two milder there.
It's showy enough for the man-in-the-street to notice. And the dense-to-the-ground habit is always a welcome change from the bare-kneed profile of shrubs like lilacs or roses.
And hey, those flowers!
Surprising enough that, for once, I wish I had a Sherlock Holmesian magnifying glass in the house.
But it's saying something that my sophora is still in a pot. It still hasn't found a home in my garden. This is partly because I'm wary of planting it in one of my "regular" beds, which might be too wet in the Winter. And yet my special good-drainage beds are comparatively few—right around the dining terrace, basically—and there's not room for a bush that will otherwise get as large as any determined azalea. Perhaps the solution is to grow the bush up into a standard. A dense ball of that ferny foliage, four or five feet up on a trunk, frothed in Spring with the unique flowers: It would be a singular as well as small-footprint display. And pleasing all Summer long, when the terrace really gets the use. OK: The first step to a standard is to start staking. To pick the stem that will become the trunk. I'll think of where to plant it, and do that in Spring 2011.