Border watering can be split in to two categories. Watering the border with sprayers and watering the border with drippers. Spray watering a border is very cost effective as large areas can be watered very cheaply. It is however very wasteful because the water is applied quickly and randomly. On top of this spray watering the border can damage the plants and leaves and will damage the flowers.
A more effective for of border watering is a pressure compensated drip pipe. The advantage is that the water is applied directly to the soil, it is applied over a long period of time so has time to soak in rather than run off. It waters below the foliage so no damage to the plant or the flowers.