It seems that folks are ignoring your questions. Most likely that's because this forum is for edible figs. Need to add enough to saturate the entire rootball and to have at least 10% run off. Anyway, I suspect the 1.5 cups of water has the tree on a very stingy diet. Also, the tinted window is a problem in that it allows barely any suitable light through for a live plant. Suggest you go to the Houseplant Forum for more responses. Go to http://forums2.gardenweb.com/forums/houseplt

It depends. Treated municipal water might contain chlorine (often not the kind that dissipates after the water stands for a while), and hard water can cause harmful mineral deposits, but you can avoid that by flushing the soil frequently. Still, rainwater or R/O (reverse osmosis) water is great, especially to flush accumulated mineral deposits from soil. Just be aware that if your ficus's roots can't take up water at all, either because they've died of dehydration or from suffocation because water retentive soil stayed soggy for long periods of time, even the purest water won't help. That being said, one of the easiest things to start with is flushing the soil to remove mineral deposits, and R/O or rainwater make that easier. I used R/O water from a supermarket machine to flush my plants, but when I'm not up to hauling stuff I use tap water from my faucet mounted filter. Once you've done that, learned how to tell your plans actually needs water before watering, and learned how to remove as much perched water as possible after watering, you can focus on getting your ficus into a fast draining soil that doesn't pose a danger to its roots. Another excellent thread called Dealing with water retentive soils: http://forums2.gardenweb.com/discussions/1415041/dealing-with-water-retentive-soils?n=62

If you clean the tip of your moisture meter and dip it in a cup of distilled water, the meter will tell you the water is dry; this because the meter actually measures electrical conductivity. So if you have a given volume of water in a given soil, the higher the TDS (total dissolved solids or roughly - salts) the wetter the moisture meter will tell you the soil is. A wooden dowel, used as a 'tell' is more reliable. If I do heavy root work on tropicals, I habitually reduce the canopy by a very large fraction to keep the plant from A) collapsing, or B) from shedding branches that might be an important part of the composition I'm building. Example: From this root mass to this:You can see the huge roots I severed, and that was only the first rootwork session. Since then, I've pruned the root mass back to just about even with the soil level in the image below. We actually have a tool designed specifically for this chore, called (what else?) a root cutter. The tree is F benjamina. The foliage mass, on the same day, went from this: To this: I'm not sure what this means: There is no other location that's suitable for this big tree. Given this condition, should I supplement the lack of light with the Dyna-Gro in a month or so? You can't counter or remedy a lack of light by supplying fertilizer. In fact, you need to be careful about not over-fertilizing in low light conditions. Dyna-Gro's Foliage-Pro 9-3-6 is a good choice for low light conditions though, because it's nitrogen sources tend to reduce likelihood of the coarse growth that occurs when using fertilizers that get their N from urea. More about using a 'tell' please forgive the weird formatting, which happens on all the word documents I write and save to share): Over-watering saps vitality and is one of the most common plant assassins, so learning to avoid it is worth the small effort. Plants make and store their own energy source – photosynthate - (sugar/glucose). Functioning roots need energy to drive their metabolic processes, and in order to get it, they use oxygen to burn (oxidize) their food. From this, we can see that terrestrial plants need air (oxygen) in the soil to drive root function. Many off-the-shelf soils hold too much water and not enough air to support good root health, which is a prerequisite to a healthy plant. Watering in small sips leads to a build-up of dissolved solids (salts) in the soil, which limits a plant's ability to absorb water – so watering in sips simply moves us to the other horn of a dilemma. It creates another problem that requires resolution. Better, would be to simply adopt a soil that drains well enough to allow watering to beyond the saturation point, so we're flushing the soil of accumulating dissolved solids whenever we water; this, w/o the plant being forced to pay a tax in the form of reduced vitality, due to prolong periods of soil saturation. Sometimes, though, that's not a course we can immediately steer, which makes controlling how often we water a very important factor. In many cases, we can judge whether or not a planting needs watering by hefting the pot. This is especially true if the pot is made from light material, like plastic, but doesn't work (as) well when the pot is made from heavier material, like clay, or when the size/weight of the pot precludes grabbing it with one hand to judge its weight and gauge the need for water. Fingers stuck an inch or two into the soil work ok for shallow pots, but not for deep pots. Deep pots might have 3 or more inches of soil that feels totally dry, while the lower several inches of the soil is 100% saturated. Obviously, the lack of oxygen in the root zone situation can wreak havoc with root health and cause the loss of a very notable measure of your plant's potential. Inexpensive watering meters don't even measure moisture levels, they measure electrical conductivity. Clean the tip and insert it into a cup of distilled water and witness the fact it reads 'DRY'. One of the most reliable methods of checking a planting's need for water is using a 'tell'. You can use a bamboo skewer in a pinch, but a wooden dowel rod of about 5/16” (75-85mm) would work better. They usually come 48” (120cm) long and can usually be cut in half and serve as a pair. Sharpen all 4 ends in a pencil sharpener and slightly blunt the tip so it's about the diameter of the head on a straight pin. Push the wooden tell deep into the soil. Don't worry, it won't harm the root system. If the plant is quite root-bound, you might need to try several places until you find one where you can push it all the way to the pot's bottom. Leave it a few seconds, then withdraw it and inspect the tip for moisture. For most plantings, withhold water until the tell comes out dry or nearly so. If you see signs of wilting, adjust the interval between waterings so drought stress isn't a recurring issue. Al

Leaves shed due to any of several potential causes. Older leaves shedding is often from a decrease in light levels that occurred in the not too distant past, nutritional deficiencies of the mobile nutrients in particular (N, P, K, Mg mainly), root congestion, a high level of dissolved solids (salts) in the soil solution, or root congestion are the most common causes. Chill, and especially sudden chill is also causal when we get into the colder months. Though it might initially seem strange, a drought response from over-watering or under-watering is also a major cause of shedding. Over-watering inhibits the plant's ability to take up water; this, due to an insufficient supply of oxygen needed to drive the uptake process. When we over-water, the plant's chemical messengers tell plant central that it better initiate the survival mechanism of acting to limit respirational water loss by shedding leaves. Make sure you're monitoring moisture levels carefully with something other than your finger. It's much more important to have an idea of what moisture conditions are deep in the pot than an inch or two below the surface, and to withhold water until the soil is nearly dry. Using a wooden dowel as a 'tell' is very effective. If you want me to post something I wrote a while back about using a 'tell', tell me and I'll hop to it. Al