Question
Greetings,

I found your name on Allexperts.com and was hoping you could help.  So far no one I have tried so far has been knowledgeable enough.

We purchased a "Black Aralia" (polyscias balfouriana) as is indicated on the side of the pot.  We have owned it a little over one year with a variety of success.  It is in a 14-inch pot, is slightly taller than 8 feet tall, and is oval in shape.  In the narrow direction is it approximately 24 inches wide; and 36 inches wide in the wider direction.  It has 7 main "trunks" and they vary in size from 3/4 inches in diameter to 1.5 inches in diameter, with 5 of them closer to 1 inch in diameter.

The plant is located in our sunroom, with an ESE orientation and a predominantly open blind situation from 3 feet off the ground to 7 feet.  Sun comes in those windows from sunrise to about 11 AM with less in the winter.  We live in the Chicago area and the sunroom pokes out away from the rest of the house.  So in the winter the average temperature in the room is mid to upper 60s and in the summer in the mid 70s.  In the winter the humidity gets to as low as 20% and in the summer is closer to 40%.

The other locations in the home where we might house the plant with a warmer temperature in the winter would have substantially less sun.

We have a problem with leaf loss.  Though the plant always continues to sprout new leaves, it drops leaves in spurts much faster than it grows them.  Though not near dying, the plant has much thinner foliage than when we purchased it.  Only the top 3 to 5 inches of each branch is "green" while the rest of the branches/trunks are tan and look more like "wood."

We had heard that most Aralias die from over watering.  Perhaps we have erred in the other direction.  ??  When we first started we watered it a very small amount each week.  Starting last fall, we started watering it every other week, but more intensely.  We never let the plant sit in water and always make sure that all is absorbed by the soil.  This seemed to work well through the winter, but now that spring has hit, we are losing leaves in record amounts.  We have never added any kind of fertilizer or plant food.

Do you have any suggestions.  Any advice you could give us would be greatly appreciated.

Kevin

Answer
Dear Kevin,

My haven't you done well to have your plant grow more than 8ft tall - I can understand your dismay to see so much leaf drop.  Are the leaves dropping from the base of the plant or all over I wonder?

Personally I would not have the plant standing in direct sun although the room temperature is fine.  As this plant has large leaves [it is known here as the Dinner Plate Aralia because of the size of the leaves] it can dry out very quickly so it is always a good idea to sponge the leaves to remove dust and then to mist them and do this frequently during the summer.

If you have read any of my answers to other plant lovers you will see that I am a great lover of immersing pots in tepid water so that they get a thorough watering.  But first of all insert a stick - I use wooden chop sticks - to see if the soil further down the pot is wet.  It may be that the top soil has dried out but it is wet lower down and therefore it is better to wait until it is a bit drier before watering.  In the winter it will need considerably less water.

Perhaps you can get someone to help you remove the plant from its pot to see if it is pot bound - if so then choose a plant pot just 2 inches larger in diameter than the new one.  Check this before you water the plant as it will be easier to remove from the pot when the soil is dry and light.

One important thing you mention is feeding - all non flowering house plants need feeding during the growing season i.e. Spring and Summer, so feed your plant fortnightly and hopefully the quality of the leaves will improve given time.  I think the plant has just used up all the goodness in the soil and is cryng out for some plant food and fresh compost.

Imagine if you were sitting in the sun every morning with no breakfast and not much water you might keel over too!  So, hopefully a new position out of the sun, regular misting and feeding [and perhaps a larger pot] will put a spring in the step, figuratively speaking, of your plant - I do hope so.  

Diana