note the new growth looks fine ...

and being that small.. i might guess transplant shock from when you planted them.. 3 or 4 leaves back in time ...

some mulch might also help ... to keep the sun from baking the soil.. and hence the leaves ...

which might also indicate a lack of hardening off prior to planting .. taking them from some greenhouse to planting in much more sun with less ambient humidity ...

new growth looks fine.. thats my key.. and soon enough ... it will outgrow and hide the problem leaves .. or just pinch them out if they are bugging you ...

ken

No info to go on here, where you are, how long the plants have been in that spot, amount of light...

Thanks folks for chiming in! More info...... They've been planted about four week & receive about 4-5 hours of morning sun with filtered light the remainder of the day...... Tilled in a small amount of 12-12-12 before planting.... Plants started out doing well, but growth has seemingly slowed & leaf damage has appeared.... Have grown Imps successfully in this bed, so I can't imagine lack of sun being an issue......

That all sounds pretty good. Maybe this is from a little fertilizer burn while adjusting. I see that they are wet in the pic. How often are you watering? If you're able to water early AM, that's usually best, instead of plants being wet all night. (Also good since, on other plants that might wilt, you're able to see if plants perked up overnight, and know you if saw faux wilt from heat the previous afternoon/evening, or real wilt from thirst.) Begonias are fairly succulent, don't wilt unless a few hours from death, so you'd want to feel for firmness to gauge their thirst. Waiting for a begonia to wilt before watering would be way too long.

I'd go ahead & remove the damaged leaves, a few per day until they're gone, 'cuz they're fugly, and to allow light to the new foliage coming along underneath. And in case it's a surface pathogen.

Thanks Tiffany! Yeah, they had just been watered that morning in the pic.... Haven't tried a fungicide........ I propagate my own annuals/vegetables & these begonias were taken from my GH & directly planted out without any hardening off, as were my other annuals, which showed no ill effects...... As I said, initially they looked fine, but they seemed to stop growing, then the leaves began to deteriorate...... Since they're light feeders, I suppose it could be fertilizer burn...... That was my first thought.....

Thanks dowlinggram! Very useful info! I use drip irrigation in my vegetable garden(s)......... Perhaps I should set this bed up for drip, now that I know begonias don't like overhead watering.........

yes.. a lot of peeps think their plants need a good shower every day ... crikey ... they need wet roots.. not wet leaves ..

ESPECIALLY if you are watering in the evening ... it is NOT good for your plants to go into dark humid nights with wet leaves ..

i used to water after dinner.. showering everything... what a nightmare.. lol .. powdery mildew everywhere ...

and that was also when i discovered the breaker bar.. aka water wand ...

mulch also helps.. so that soil is not thrown up on the plants .. in other words.. soil borne problems ...

i also would NOT till in plant food ... unless a soil test indicated something lacking from your soil ... which LOOKS pretty darn nice ...in fact.. i would skip the tilling completely .. and just add compost .. and build a good friable soil [of course if you go that direction.. you dont use the mulch]

but once planted .. a LITTLE of this or that wont hurt ... just keep in mind.. this is not a production crop requiring heavy fert'ing ... as are most flowers ...

ken

Thanks Ken! You're spot on here...... I have a few chickens plus a compost bin, sooo ... all my beds & raised beds have marvelous tilth, but a soil analysis shows it lacks N & is high in P & K with a Ph of 7.3, (a bit high for most vegetable apps..........) Little Urea & Sulfur correct this problem......