Question
I have had Norfolk pine trees for 19 years. I have had 2 total. They are both In pots. My sister now has the first one I got 19 years ago because it got to big for my apartment patio. The one I have now I've had four years. It is at least 6 feet tall and I'm not sure of the size pot it is in but is in pretty good size. My concern and question is my brothers cat used it several times as a cat box. My brother did not pay attention to what his cat was doing out there but left him out there for several hours without a cat box. I have sense put in large rocks so the can not get in there anymore. The tree gets watered once a week. The lowest branches look like their starting to turn color and I didn't notice if they had been doing that prior to the cat going pee in the pot. I live on the second floor and can not soak it with enough water to try and wash it out. I thought about taking out the soil and replacing it with brand new fresh soil. Do you have any suggestions what to do and help me save my tree. Thank you
         Rebecca myers

Answer
Rebecca,

These plants have very specific needs: Light: They prefer full sun and tend to stretch out in dimmer conditions (see below). Give your plant the best light possible, or alternate between full sun and short periods in dimmer conditions.
Water: They are somewhat drought-tolerant, so they are a bit more forgiving where water is concerned and in fact it is advisable to let the soil dry out fairly well between each  watering.
Soil: These are acid-loving plants, with a preferred pH of about 5.5 or even 4.5. A peat-based mixture is perfect for them as the mix will gradually acidify as the peat breaks down.
Fertilizer: Feed with a weak liquid fertilizer throughout the growing season, although you may have to suspend fertilizing in low-light periods. Cat urine and feces acts as fertilizer and is a soil acidifier. Do not add additional fertilizer for 6 months and the cat feces and urine should not be a major problem.
I suspect that your problem with yellowing is coming from over watering. This plant absolutely needs to dry out between waterings and not be constantly wet. To monitor water closely insert a bamboo skewer or a dowell rod into the soil all the way to the bottom of the pot and cut it off 1/2 inch above the soil line with scissors or wire cutters. When you think the plant needs water pull the skewer out and see if the top half of the skewer is dry. If it is not put the skewer back in the pot and wait several more days and check again. If it is dry give it enough water so most of the soil in the pot gets moist but very little if any of the water goes into the drain tray. An hour later empty all the water out of the drain tray so the plant is not sitting in water. If you can't lift the plant to empty the drain tray use a turkey baster to suction it out. That would rot those fine roots. You should only need to water it once every two weeks or less.
Too keep the plant froby m getting too large for your apartment instead of repotting it into a new larger pot every few years remove it from the pot and cut one to two inches off the root ball all the way around and put it back in the pot with fresh soil. That will give the roots room to grow without the tree growing a lot larger. You can also slow down the top growth of the tree by removing 1/2 of the new growth in the fresh new light green stage each spring simply by pinching out half to 2/3rds of the new light green growth. That will slow the growth of the already slow growing tree.
If you have more questions about the use of these techniques feel free to write again. Good luck!

Darlene