Clumps of camassia, blooming their blue heads off on a rainy April Monday at Fort Tryon Park, the far North of Manhattan.
That's the Hudson and Jersey in the background; it's a spectactular site.
"Big" is a relative thing, but read on. There are only a few blue-blooming Spring bulbs—scilla, muscari, crocuses, hyacinths, and these early-early Iris reticulata, which, yes, grow from bulbs.
Hyacinths aren't worth it past the first Spring anyway, so let's toss them as being what they truly are, a splurge for municipal garden bedding.
In cost-conscious gardens, then, all the other Spring blues are ankle-biters: Four inches, six inches, tops. Except camassia. Shin-high, it's the giant among them. And it's staying power is unrivaled. When it likes you, or rather the land you have to offer it, it can self-seed to the horizon.

Here's a meadow-full in Idaho. How happy are we. (Read more, and see the picture even bigger, here @ Wikipedia.) Other species of camassia are even bigger blue, and can tickle your knees. Most important for me with my flatter-than-Holland land, they are exceptional in their easy-going approach to wet ground, even growing pond-side. That's my garden after Winter rains. Camassia are in my future.

Evergreen deer-proof groundcovers are scarce. (Think about it: deer will demolish pachysandra and ivy. Only vinca has potential to cover a reasonable amount of space effectively.)
So "Sweet Box" is important. It's congenial too, spreading slowing (yes, often too slowly) but steadily. (If you have ever had opportunity to dig up some, you'll be shocked, shocked, at the profusion of horizontal white stolons you'll expose. You'd think the plant would be spreading with the speed and ruthlessness of bamboo. We wish.)
Instead it's more like the Little Engine That Could. You plant pots of it, oh, two feet apart, closer if you can afford it, and they merge with the speed of a tai-chi group. If you worry about how they're doing, they don't seem to get anywhere. But then (well, a few years later), you've got a colony like this one at one of my client's:

If you spend a lot of time on your knees near your colony, or are just a munchkin, you'll pick up a Fall talent: pleasantly fragrant flowers. Hence the "sweet" box thing. (Of course, the plant doesn't look a thing like box, which has much smaller as well as rounded leaves, and doesn't spread underground either.)
The flowerbuds are in the crotches of the leaves. The display is all nasal, so to speak, not visual. You won't see that the bush is blooming, but (if you're at that low altitude at least), you'll sure smell it.
Oh yes: What a fun latin name: Sarcococca. It even sounds like the Little Engine That Could: SARcococca, SARcococca, SARcococca, SARcococca. The second name, "humilis", echoes "humility". The bush is unassuming and hardworking, with a low profile. Humility indeed.
Of course there's a catch: sarcococca isn't as hardy as we'd all like. Zone 6 only, and even so, you're doomed if it doesn't have great Winter drainage. I've proved this in my own gardens. I'll try again with sarcococca, but in my modestly-but-effectively-raised terrace beds. Even an couple of inches of raised-bed-ness can do the trick: Any little elevation will ensure that the water slides off the bed instead of sitting around helping everything rot.
Here in New England, sarcococca is Spring-plant only, so I'd better get cracking. Got it.

It's a long time in "Spring" before the mainstream "Spring" stuff like rhodies and azaleas get going. It's actually hot out. For Spring when it's chilly and still making up its mind—which is, I'd think, when we all need Spring the most—look farther.
No, farther even than forsythia. Your neighbor has that already anyway.
Corylopsis bloom even earlier than forsythia, with more nuanced flowers followed (as I'll post later), unlike forsythia, by dynamite foliage. (I'll post when this bush's foliage comes out.) And the branching is better than forsythia too: Strong horizontals as well as strong verticals. Corylopsis can be big—ten even fifteen feet wide as well as tall—but unlike forsythia they never come across as just a dump of twigs waiting for the compost heap.But first the flowers:
Here's a mature Corylopsis pauciflora from a client's garden. Click to enlarge it—the details are so satisfying. (There are several other species. It's not important to get worked up about which particular one; pauciflora is hardy and, for a corylopsis, not overly big. So it's a great one to start with. In this regard, then, it's the counterpart of Hamamelis "Arnold Promise": foolproof and glad-to-see you. If you only have one hamamelis, Arnold Promise is a great one to have. Only one corylopsis? Do pauciflora.)
The flowers are in pendant chains, a soft yellow-green instead of the sunglass-inducing chrome yellow of forsythia. They are fragrant too, although it's not a penetrating, traveling, "watch it roll toward you" fragrance like with Daphne mezereum, true. But continuing my theme (I see) of honoring plants that are stylish stalwarts when any garden needs them the most, I say that you should just get out there in the chill and drizzle and bring your nose to your corylopsis. It's working hard (but with joy), so give back a little effort in return.
But why not corylopsis from my own garden? Well, one or two are on the plans—but for areas that are only this year getting transformed from Before (i.e., ignored mess) to After (gardens). And even the small corylopsis ain't small enough. Until, that is, I discovered Corylopsis gotoana 'March Jewel', which gets only eighteen inches high (and yes, five feet across, so it's only dwarf in one dimension). I hope to snag one of those this Fall, unless you beat me to it at Camellia Forest nursery.

Who knows why this plant is that color? Height? Fussiness? It makes sense to the plant somehow; we can only enjoy and enthuse.
This groundcover-bamboo, hardy into Zone 5, relinquishes the outer half-inch edge of its leaves when the weather gets cold. The cells die, the green fades, and the parchment-colored cellulose structure is left behind—while the center of the leaf is kept alive through the Winter.
It's a stunning show both close-up at en masse, especially in mild Winters when, indeed, the center of the leaves remain viable.
In more serious Winters the entire foliage is liable to "parchment out". Not a terrible display, just not as singular. No matter if it's a mild Winter or a nasty one, by Spring the entire colony gets cut right down to the ground. The parchmented leaves don't "recolonize" their dead edge, and it's best to get rid of those stems entirely; the new crop of stems will be plenty profuse. My colony here—at the same client blessed with the tap-dancing stinking hellebores, is about ten years old, and all the stems you see here are indeed just from the previous season's growth.
This bamboo is Sasa veitchii ("sasa VITE-chai"). I don't yet have it planted in my own gardens, silly me. The Winter show is exceptional, so it would be best somewhere I can see it en route to of even from the house during the cold months.
But those beds are (duh) already crammed with other beauties, and this bamboo likes to wander. Perhaps—I know—in a big container, where I can enjoy the foliage show for a while but by, say, January, hustle the pot into the greenhouse. (Sasa isn't hardy enough to survive in a pot through the Winter.) A thought, but a weighty one: Yet one more container to lug into cover for the Winter and out again for the Summer. Sigh. I'll consider it.

Checking out a client's garden nearby in Connecticut—which had (like all client gardens, where the owners, by definition, have a life much apart from their gardens) been left to itself all Winter long—I was startled, no thrilled, by this irrepressible colony of "stinking hellebores."
This evergreen perennial must be disgusting to the taste, or poisonous as hell, or both, because deer leave it strictly along too. It can start blooming in December, continuing all Winter long despite getting covered by snow and ice. And withal, here it is happy as ever, with big heads of blossoms the color of granny-smith apples that are only at the very early stage of considering a fling with celadon.
The blossoms clusters are cuttable too, so you don't have to trudge out through the snow and into the cold to enjoy them.
I had this strategy at my house, planting a few stinking hellebores right along the pathway to my back door. But the plants pooped out. Judging by this energetic and completely self-confident client colony, this hellebore delights in full sun (which I didn't provide) and craves or even requires fabulous Winter drainage, which is always a question with my too-flat ground and occasional Winter floods. My rich heavy soil only makes the sketchy drainage worse. I just try again, giving this plant what it needs to thrive regardless if that location is near the door or even easily accessible in the Winter. A show this Winter-defiant, this "singing in the rain" is worthy of visit. It demands to be honored by a viewing that doesn't just entail but actually requires of we lowly humans a galoshes-and-heavy-coat trek. And by god I'll do so: honor this astounding plant with pleasure and with humility.
PS: That "stinking" hellebore name? A mystery to me. No stink anywhere near, on, or emanating from this beauty. Who knows otherwise? Thanks, truly, for your education.