Garden Q&A

Question:

Can we transplant and divide large established hostas now?

- R. and K.D.

Answer:

Yes. The optimum times are fall or early spring, when new growth is just emerging from the ground. But hostas are tough, and if you're comfortable with an awkward-looking plant for a few weeks, go ahead.

Actually, I would divide first, then transplant. That is, get a straight, squared-off spade and place it vertically in the center of the hosta, trying to get the foliage neatly parted to each side. Then, using a lot of force, cut straight down with the spade. Old hostas develop exceptionally rugged centers, so this cutting action may necessitate basically jumping onto the shoulders of the spade with both feet. Complete the cut to the edges. If you think the plant is large enough, repeat, cutting it into quarters.

Next, to save as much foliage as possible, use some twine to gently tie up the leaves of each segment. Then dig around the clump and remove the segments. I prefer a sturdy garden fork for this, so that you cut as few roots as possible, having just cut substantial roots in the center.

The holes at the new sites should be big and deep - this is one case where going overboard is a good idea. Hostas respond best to deep, rich soil. If yours is so-so (or sandy), get lots of compost or municipal sewage sludge to mix with the soil removed from the hole. Use the rich soil to bring the bottom of the hole up to the proper height for the transplantee, place it, then backfill with rich soil.

Keep transplants watered for the first few weeks, and even so, do not be surprised at loss of some foliage - cutting through the center kills or severely sets back a few of the divisions, as hostaphiles call the individual crown from which a set of leaves grows.

Q:

Last year, I planted bachelor's buttons and Sweet William plants. They survived the winter, and bachelor's buttons are now blooming. Should the dead blooms be cut from both?

- Lou Goodman

A:

Mild winters - the trend of late, though not something to count on - can result in the survival of "annuals" and tender perennials. I use the quotation marks because many, many plants that we grow as annuals are actually perennials in milder climates. So, when it's mild here, they may act perennially.

Sweet William,

Dianthus barbatus

, is definitely in this group. "Short-lived perennial" is its typical category (thus, when it dies over winter, the gardener doesn't assume he or she has done it in via neglect or abuse). One way to encourage Sweet William to behave like a perennial is to cut it back a third or so after blooming, so that no energy is wasted on seed production. But then, if you do let it go to seed, you'll likely get many self-sown plants for the next season.

As for bachelor's buttons,

Centaurea cyanus

, I'd say: Lucky you! Your bachelor's buttons overwintered. Don't expect it again. Unless, of course, these are actually self-sown seedlings, since bachelor's buttons are well-known for self-seeding.

So the answer about removing spent flowers of both of these depends on whether you want self-sown (free) seedlings for next year.