IN LATE WINTER ‘YOU JUST TRY TO KEEP THEM BARELY ALIVE,’ Mobee Weinstein said when we met at a professional event one recent February.  I was lamenting my winter-weary collection back at home, and consoled to hear from a pro that I wasn’t abusing my begonias, plants that Mobee, longtime foreman of gardeners for the New York Botanical Garden, introduced me to early on in our gardening careers. My begonias are at their lowpoint foliage-wise around then but some are always flowering anyhow—’tis the season. What courageous, forgiving members of my household and garden.

I just call them all fancy-leaf begonias, but they divide into several structural groups:

• Fibrous-rooted ones have cane-like stems and often wing-like leaves.
• Rhizomatous types grow from fleshy, caterpillar-like structures inclined to spread over the pot lips or even stand upward.
• The extra-flashy Rex begonias, which are a little trickier if you get too cool or too hot since they may defoliate in protest, are rhizomatous. I fail with them; my conditions are not to their liking.
• There are also semi-tuberous and tuberous begonias, with swollen bases, but my collection doesn’t include any right now.

Though I am not in Zone 10 (minimum temperature 30-40 degrees F), where they’d be hardy, fancy-leaf begonias play an important role in my summer garden, anyhow, spending some of May through September or so outdoors, weather permitting. They love those months of high humidity, growing happily in the filtered light to the east of the house (above) where they spare me from buying lots of annuals for “color” along the front path, thanks to their spectacular leaves. My potted begonias provide most of the color I need.

In the offseason, the begonias are a little less thrilled with our shared digs, since low humidity with the heat on and drafty, cold spots under 55ish degrees are not to their liking. They also want bright light, which is hard during Northeast winters. Supplemental fluorescent lighting, and perhaps a humidifier, would make them happier, but we’ve managed anyhow for years; some of the ones I grow as houseplants in winter have been with me a decade or more. (One newer acquisition, from Logee’s, is the very showy orange-leafed ‘Autumn Ember,’ below.)

What they dislike:

• Low humidity, especially when 75-plus.
• Temperatures under high-50s or better yet, 60 (this is where I fail; my brightest winter spots are in the too-cool-for-comfort mudroom).
• Wet feet or soggy soil, ever (no standing in saucers of water, or watering before dry).
• Overpotting.

What they love:

• Humidity.
• Bright light, such as a west window or bright east one. A few hours of direct sun offseason; filtered in summer. Rexes can manage with a little less, generally.
• Feeding weakly, weekly, in periods of active growth. I do not feed Octoberish to sometime in February.
• Less water in winter (once weekly is usually plenty in my conditions).
• Pinching tips of young plants to promote fullness, such as when a caterpillar-like rhizome wants to jump out and over the lip of the pot. (With fibrous types, you can prune anytime things are headed out of control.)
• More from the American Begonia Society.

My favorite easy fancy-leaf begonias:

‘Marmaduke’ (above right) is a rhizomatous type; a robust grower with the most spectacular dimpled leaves that are chartreuse-spotted-in-red. Officially listed at 12-16 inches tall, my bigger of two plants is twice that, and wider.

‘Little Brother Montgomery:’ Though the catalogs say this fibrous cane type gets to 16 inches tall (true in a small pot), my oldest ‘Little Brother’ is really a ‘Big Brother’—a shrub-sized thing of more than 3 feet high and wide (not counting the 14-inch-wide pot). Leaves are Rex-like, patterned like stained glass in bronzey-green, reddish and silvery-gray (see leaf details, near bottom of the page). Put two or three plants in a 14-inch pot and you’ll have a shrub in no time.

‘Black Fancy’ is rhizomatous, but more compact than ‘Marmaduke’ and with the deepest-color, smooth leaves that have wine-colored undersides. ‘Kit Kat’ has smallish bronze-green leaves spotted in chartreuse; ‘Palomar Prince’ is dark green with splashes of lighter green, the leaves deeply cut.

Want a longer list of possibilities? Houseplant expert Tovah Martin gave me hers in this interview, with her growing tips, too.

Propagating begonias:

Whether from pieces of rhizome, leaves, tips or stems, many fancy-leaf begonias are easy to propagate. I could not do better than the expert of all experts, Brad Thompson, in explaining how.

Fancy-leaf begonia sources:

• Logee’s sells both rhizomatous and fibrous types, along with the Rex’s and some tuberous ones, too. (That’s a detail of ‘Little Brother Montgomery,’ above.)
• Kartuz has all classes, including the the famous Thompson hybrids.

Begonias look great indoors and out with ferns, of course—a classic Victorian combination—and my friend Mobee from NYBG is expert on those, too. Do I sense another houseplant collection in my future?