Swish, I'm not sure I understand when you say the wheatgrass doesn't have time to grow.
Anyways, here are my instructions on growing wheatgrass.
Soak your hard red winter wheatberries in filtered water for 10-12 hours. 2 1/2 cups of wheatberries will expand to 3 cups after being soaked, and that is enough for one square tray of wheatgrass (you can use the plastic trays you buy at Home Depot or any nursery. They are 17 inches square.) Bury the seeds just under the soil. I use Super Soil. Keep the tray covered for 3 days. They need to grow in darkness for the first 3 days. To keep them dark you can invert another square tray, and put it on top of your tray of wheatgrass. Water the wheatgrass every day until the bottom of the flat begins to drip. Grow the wheatgrass for aproximately 3 more days in indirect light, watering every day. The wheatgrass is ready when it is 8" tall.
Wheatgrass can be grown indoors or outdoors. A temperature of 68-75 degrees is ideal. One tray of wheatgrass will yield about 16 ounces of juice on average. When harvesting the wheatgrass, cut it as close to the soil as possible (the nutrients are most concentrated at the bottom), and juice it immediately. Or you can cut it and refrigerate the blades, and they will keep for up to a week. After juicing, drink the wheatgrass immediately. The enzymes and nutrients begin to die after 15-20 minutes.
"Non-violence leads to the highest ethics, which is the goal of all evolution. Until we stop harming all other living beings, we are still savages." Thomas A. Edison