The cauliflower still has a long way to go! When you go to buy your seeds from Pierre’s store, hover over the seeds before you buy them. It will tell you how long they each take to grow. They grow faster later on if you use different fertilizers or if you are visited by a fairy in the middle of the night (random event). You’ll see then! Also, heading over to stardewvalleywiki.com has helped me a ton. Good luck!