No need to buy weed and feed. Can do both functions separately. In fact the granular stuff doesn't work unless the lawn is wet. This attaches to your hose and you can spray it just where you need it. It won't kill crabgrass unless crabgrass has emerged already. It kills most of the weeds by growing them to death: using 2-4-D an auxin I used in college to cause strange growths. When you prune plants auxins are released to encourage new growth. Gotta respect the complexity of plants. New research indicates they can actually learn, as well as discern gravity, day-length, time of day, moisture, temperature, and communicate with each other.
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