Question
I was hoping you could please help me. I have two balcony containers with ivy, begonias, and violets. In the last couple of weeks, I noticed that the begonias (one in particular) have been very weak. The leaves have stopped growing, faded somewhat (not necessarily dry, but weak and faded), and the blooms keep wilting (the edges brown and few new blooms are forming). They are tuberous begonias, the ones with the smaller blooms. Oh, and they're on a balcony ledge facing east.

I have spoken to a couple of local flower vendors, and they both told me that it could be a result of the (lots and lots) of rain we've been having lately (I live in Montreal). But I didn't get it, as the begonias in the second container get the exact same treatment, and they're flourishing. So it occured to me that it could be the soil. When I was potting these, I ran out of the good soil and added some cheaper stuff I had purchased for something else, then mixed it with peat moss to fill up the containers properly. So I am now thinking...

a) the soil is too heavy as a whole (I've noticed that the "sick" pot doesn't seem to drain as freely when I water the plants);

b) I added too much peat moss and the soil is too acidic (there actually is a green mossy film on the top of the soil, which i read in a previous posting could mean that it's acidic).

For now, I have taken the one begonia out (I was advised to let its soil dry out, and then water it less frequently to see how it does). And I was hoping you could help me with what to do next. I guess my question (sorry, questions) are:

1. how can I improve the soil other than by changing it entirely? The ivy and violets still in the container are doing fine. Can I add some sand to dry it out a bit? Some perlite?

2. if the begonia does improve, can I put it back in this (new) soil?

3. if, heaven forbid, it doesn't improve and I lose them... any suggestions as to what kind of flowering plant does well in such conditions?

Answer
Hi Jane,  Since you think soil is the problem, then that's the first and immediate thing we should change.  Repot any plant that is not thriving into a lightweight container mix potting soil.  Remember to dump out any excess water in the saucer after you water or after it rains.
Don't try to fix what's broke by adding to the poor soil.  Dump it out and start over.
If you lose them, write me back and we'll discuss hardier plants.   For the time being, think positive, they are going to survive!  Jim