I have been taking care of my basil plant for quite some time but I noticed that the bottom stems are wooding. Every time I look it up it either says it’s maturing or has root rot. But the wooding is climbing up the stem and some of the bottom leaves are turning a really light green and then falling off. Is this normal? Two of the pictures I took and few weeks ago and the other I took today. The brown is crawling up the stem. I also tried to take I picture of a leaf that is much light of a color than the rest.