You really need to include your state and USDA zone in your user info. It makes it much easier to assess your situation & offer specific advice.

First, the owner of the plant shop certainly bears the lions share of the responsibility for the sorry state of affairs your plant is in by virtue of the horrid advice offered (unless you misunderstood it). Ficus b reacts to saturated soils fairly quickly with a drought response. Root function/metabolism is adversely affected by anaerobic conditions (saturated soil), and roots rot when the plant is allowed to sit in standing water. In either case, leaf abscission is virtually guaranteed if the condition is not corrected quickly.

Reduction in light levels between the plant shop and your home can also cause the leaf abscission either as a lone or contributing cause. Sudden chill can also singularly or as a contributor cause leaf abscission.

If you misunderstood his directions about the collection tray adding humidity, and he meant that you should raise the plant high enough so the soil does not contact the water in the collection plate, his responsibility could be argued. Also, waiting a day or two before watering again is likely not long enough. The soil should be dry to the touch at the drain hole before you water the plant.

The main issue is that your plant has divested itself of its ability to make food. It will also call on all, or almost all of its energy reserves to push a new flush of foliage, which will leave the tree with decimated energy reserves going into the most critical portion of the growth cycle - winter. Where you live, and the extent of the damage to the roots will determine whether the plant survives. I would return it for a refund & find another plant and plant store. If that is not an option, let me know & I'll help you decide the best course of action to nurse the plant through the winter.

If the plant pushes a new flush, it will have to be protected if the plant is to survive. It is highly unlikely that if something occurs to cause any substantial loss of the new foliage, that the plant will be able to recover from the loss.

Al

PS You may also find the link of some interest ...

Here is a link that might be useful: Cultural info & background

Thanks tapla for your prompt reply and insight. I live in NY state.

RE:The Shop owner's Instructions for Watering my Ficus
I did not misunderstand him. He instructed me to leave the water in the saucer until it evaporates. When I spoke with him again about the problems I was having with my Ficus plant, I mentioned that I had been reading a lot of information about how to care for a Ficus Benjamina and it all stated that I should NEVER let the plant sit in "standing water", as this will certainly cause root rot. Instead, I should make a "humidity tray" by filling the plant saucer with gravel to prevent this and to increase humidity around the plant. He replied by saying that he had been selling ficus trees for over 25 years and even have them in his home, and that he lets them sit in standing water in the saucer, without gravel or rocks, and his ficus trees are fine. If my plant does have root rot, is it reversible? Is it necessary to mist the plant daily?

RE: Lighting Conditions
The owner of the shop keeps all of his Ficus trees outside in full sun during the day. So, when I received my ficus, the lighting conditions drastically changed. The owner of the shop stated that my leaf loss was due to the fact that my ficus was adjusting to my new environment and lighting conditions. It can take at least 4 to 6 weeks (or longer) for it to acclimate and I should not worry. Is this true?

RE: Insect and Disease
Since I purchased my plant, I discovered that it has "red spider mites" and "aphids". The owner had sprayed the plant with insecticide before he deliverd it to me;so he was surprised that I had them. Additionally, several of the leaves now have black spots on them (possibly Leaf spot-a fungal disease?)So, last week I purchased a product by Schultz called "Garden Safe Fungicide 3"(3 products in one: Fungicide, Insecticide, Miticide) and sprayed my plant. A lot of new healthy leaves are still falling off.

Depite all of the problems that I'm having, there are a lot of new baby stems growing all over the plant. I'm hoping they will not dye off.

P.S. Just a correction: The shop owner instructed me to water my ficus a day or two after the runoff water has completely evaporated from the PLANT SAUCER-and not a day or two after watering the ENTIRE PLANT. I purchased a water meter to help me determine when it is time to water my ficus.

If the shop owner holds tight to the idea that his instructions were on target, I have to seriously question his expertise/judgment, regardless of his credentials or how long he has been selling plants. This is stuff that every hobby grower learns in Ficus 101, and he should know better. Scoot on over to the Houseplant Forum and ask about a watering regimen if you have reservations about accepting one person's (that would be me) ;o) assessment of your plight. I won't be offended.

"Is root rot reversible?"

I want to remain technically correct, so I have to say NO. Dead, rotted tissue is just that - DEAD. You cannot bring it back to life. Trees are not like people, in that they do not form new cells in old places - they are not regenerative. Trees are generative, which means that as they grow, they form new cells in new places. In order to correct the root rot, you'll need to depot the tree, remove the soil, and prune rotted tissues back to beyond the point where they are viable. Alternately, if you're not up to the root work, you can try depotting the plant & leaving it set on newspapers over night. This should dry the soil out & you can then return the plant to its container and begin watering appropriately as required, and hope.

"Is it necessary to mist the plant daily?"

NO There is plenty of scientific evidence to support the idea that misting is more apt to be harmful than beneficial (see my post) and refute the idea that it is necessary or even marginally effective.

"The owner of the shop keeps all of his Ficus trees outside in full sun during the day. So, when I received my ficus, the lighting conditions drastically changed. The owner of the shop stated that my leaf loss was due to the fact that my ficus was adjusting to my new environment and lighting conditions. It can take at least 4 to 6 weeks (or longer) for it to acclimate and I should not worry. Is this true?"

While it's true, as noted above, that a reduction in light levels between the outdoor conditions at the plant store and your home can cause the leaf abscission, it's NOT true that it's no cause for concern. Your plant should have more stored energy now than at any other point in the growth cycle. Instead, the tree's food-making ability has vanished with the leaves (so the tree is operating on stored energy), PLUS, the tree will have to expend nearly ALL of its energy reserves to push a new flush of growth. Your tree is much closer to needing intensive care than it is to a worry-free winter vacation.

I'm not going to go into the insect/disease thing, other than to say that the leaf 'disease' is likely a product of oedema due to over-watering. Of course he's "surprised" your plant has an insect infestation. Based on his reluctance to step up to the plate so far, I wouldn't expect any other reaction, unless it was to blame the bugs on you. ;o)

Forget the water meter. They don't measure moisture - they measure EC (electrical conductivity). To test this idea - stick the probe in a cup of distilled water and notice that it reads 'DRY'. Dissolve a tsp of salt in the water and it becomes 'WET'. It is better at measuring fertility levels (the level of dissolved solids [salts] in the soil solution) than moisture levels.

Al

UPDATE:

Al,

I took your advice and called the owner of the shop and told him that I want to return my Ficus because of all of the problems I've been having with the plant in just 30 days (leaf loss and damage, insects). He said no problem, I can return it. I want to exchange it for one of the Ficus cultivars- a Ficus Monique- which I read was recommended for first time Ficus owners becaue it is less sensitive to changes and experiences less leaf drop. For that reason, I had originally wanted to purchase the Monique, but the owner did not have any at the time.

Curiosity got the best of me so I also decided to examine the plant for root rot. I removed my ficus from the container and checked the roots. I admit, I did not examine all of the roots, but the roots I did examine were firm and not mushy. They were not black or dark brown, but were a cream to light brown color, with no foul odor emanating from the roots or soil. The soil was also a tad moist so I also watered the plant. It had been nine days since I last watered it and I decided to let the soil almost dry out out of fear of over watering the plant.

I hope the Ficus Monique will not present as much problems as the Ficus Benjamina. Do you have any experience with either the Ficus Monique or Wintergreen?

Both 'Monique' and 'Wintergreen' are cultivars of the species benjamina - and have the same cultural wants/needs.

Roots exposed to saturated soil conditions can lose leaves for more than one reason, and roots rot in a predictable order, the finest and most important, first. In the case of rotted roots the tree is unable to move water to the canopy & the tree responds as if it is in drought conditions, shedding parts (leaves, twigs, branches) to minimize additional water loss via transpiration. A change to lower light and/or anaerobic (no air in the soil) soil conditions impedes photosynthesis. Since a steady supply of auxin (a growth regulator/hormone) flowing from leaves and meristems across the abscission zone (a layer of cells at the base of leaf petioles) is necessary to keep an abscission layer from forming and leaves from falling, and auxin is a by-product of photosynthesis, anything that affects photosynthesis dramatically causes leaf loss in benjamina and many other plants. The gist of what I just said is that just because you didn't detect rotted roots does not mean that root function/metabolism is not drastically impeded by the saturated soil, and the most important roots (that rot first) are hardly noticeable - almost microscopic.

Al