The holes/cuts/tears sound more like mechanical injury from poor (former?) physical treatment than anything, but that's a guess. Do you know how to check for mites/mealies/scale - will you recognize these pests? Check for them.

Depot the plant & check roots. If they are dark and soft, rank smelling instead of earthy, you'll need to bare-root and trim roots back to sound, healthy tissue. If the soil is just saturated at the bottom and roots appear sound, place the plant on a few sheets of newspaper until the soil dries down. Then, repot it and be careful about watering. Did you read the thread below that poo poos the 'any change causes defoliation' theory and lists the real reason(s) why Ficus b. defoliates?

How much difference is there in the temperature change of the room? Does it drop below 55*. What is the daytime temp range?

Al

Here is a link that might be useful: More on Ficus b. here

Ellie, can you scrape the black 'patches' off with a fingernail? Toni

Hi Al, Thanks for these suggestions and the useful link. I have not checked for pests before, but I have a book that tells me what to look for! As regards room temp, I'm not really sure... we set the heaters at 20 degrees centigrade for a couple of hours morning and evening and the rest of the time - including overnight - they are at a background temp of 12 degrees centigrade. The plant is not near to the heaters, nor by a window. Having read the link, it seems unlikely that the temperature is to blame for defoliage - as it does not seem a drastic change. You mention poor care of the plant as a possible cause of holes and tears - I don't know how it was treated previously, but it did have a bit of a traumatic journey to our flat - as we had to take it on the London underground! - so I don't know if damage could have ocurred then. The tears look sharp - like cuts, which seems strange.

Toni, yes the black patches do partially scrape off with a fingernail - but they are very sticky and it is difficult to remove the substance from leaf this way - any ideas what it could be?

Thanks again to you both, Ellie

Hi, Ellie. The 20* is pretty good, but the 12* is borderline low. Ficus has a bit of a problem with its photosynthesizing machinery as temps drop below 12 or 13* C. I agree that it's unlikely that temp is to blame for defoliation. The leaf damage does sound like injury from transportation.

The black spots, if removable with your nails, sounds like something called sooty mold growing on honeydew (insect excretions). This condition, if no mealies are apparent, would make me strongly suspect a scale infestation.

Al