Your begonia is stunning, have you ever added rocks to the boxes to weight them down? I prune my begonias to make them bushy, which isnt your problem :>), you can take cuttings from yours and make more plants or give the cuttings away. I cant think of anything off the top of my head that would be a pretty as what you have..

I don't think adding rocks to the boxes would help because the plants get very top-heavy, and if it gets really windy or we have a heavy rain I think they'll still topple over.

you can use deeper larger boxes and then lash either the frame or the box itself to the railing with wire/plastic ties.
your long planter looks rather small.

I was looking for something to plant in those boxes. I'll probably plant begonias in tall, heavy planters that sit on the deck, not in boxes that sit on the railing.

well, then may be you can plant trailing non-stop begonias into them? they should do well for you staying cool in your zone and they also bloom in part shade. but they don't get as tall as dragon wings. non-stop is a trade mark.
non-stop is a tuberous hybrid bred to bloom all summer and until frost.

Non-stop begonias look live a very good alternative. Thanks, petrushka!

Wait- before you get Non-stops, is your "part sun" morning sun, afternoon sun, or dappled all day? For me, Non-stops do beautifully in morning sun. When I tried them where they were shaded most of the day with afternoon sun, they fried.

Depending on your conditions, the various new Begonia boliviensis hybrids may be a better choice. They are also tuberous, but they can handle more sun and heat.

The "Bonfire" series has been out for a while and comes in three bright colors. They can get spectacularly huge, but are trailing so they wouldn't be top-heavy.

There's a newer series called "Crackling Fire" which stays smaller and bushier, and comes in more colors. I think "Crackling Fire" might be the right size for your planter boxes. I haven't tried them yet but was tempted by them at the nursery.

And yet another series called "Million Kisses," which I've only seen in catalogs so far.

And there's a seed-grown variety that looks similar to "Bonfire" and might stay smaller. "Santa Cruz Sunset" only comes in red-orange. I grew 6 from seed last year, which made one hanging basket because they were babies. You'd want to buy them as started plants. Seeds have to be sown by early February to have plants for summer.

The nice thing about tuberous begonias is that if you have a good spot to store them and ignore them over winter, you may be able to keep the same plants for years. They get larger each year. My "Santa Cruz" basket has revived and should fully come into its own this year. Might need a bigger basket. :-)

Oh, and I almost forgot. DragonWing has a smaller sibling, BabyWing. They only come in white or pale pink.

This post was edited by edie_h on Sun, Apr 27, 14 at 3:13

oh, nice! i haven't seen those yet in my shops! i'll keep them in mind too. my non-stops stop flowering in the heat, true! up to 75F is probably ok. then they stop. and then they start again when it cools off in the fall.

edie_h -- The shadiest and coolest part of my deck railing is shaded over by about 11:00 AM. The sunniest part is totally shady by about 3:00. That's a huge range of sun and heat and what I've been doing for a few years is rotating the boxes every couple of weeks. The dragon wing begonias that get the most sun do wilt a little in the heat of the day, but perk up as soon as the direct sun disappears.

I'm going to print out your recommendations and see if my local nursery has any of them. Thanks so much!

What about fuchsias? I'm thinking the bushy upright varieties