Growing a coat depends on its genes for growing an appropriate coat and also care too. If your yorkie has a terrier, rough feeling coat - most likely it will never grow a long coat. If it has the hard silk coat - that takes much longer to grow. A red legged yorkie will also have a hard time growing coat, especially on its legs (this usually stays short). Cotton coated yorkies grow coat, but is a lot more work to care for, since they get matted often. Of course a nice correct silk coat - grows the fastest and best. This will feel like a satin ribbon - cool to the touch.
Grass, carpet, and fabrics that your yorkie rubs up against can cut the coats.
Here is my girl when she was about 9 months old. |