Okay, so weeds will always be with us, but there are some simple tips to stay ahead of the weed race.
1. Minimize digging
Weeds seeds are everywhere in garden soil, but only those in the top several inches get enough light to germinate. Digging or turning the soil, exposes these top level weed seeds. So dig only when needed and then cover the disturbed soil with plants or mulch.
2. Use lots of mulch
Mulch helps to keep soil moist, cool, and eliminates the light that seeds need for germination. Organic mulches often harbor beneficial insects that eat or destroy weed seeds. Refresh mulch when needed so that there is 2-3 inches above the soil. For areas with heavy weed infestations, place cardboard, newspaper, or any other bio-degradeable material between the soil and the mulch. Just remember, keeping weeds at bay is an annual process since new seeds will be blown in or dropped by birds. Have a good layer of mulch makes it harder for the seeds to take hold and easier to pull if they do.
3. Weed after watering
It's always easier to pull weeds when the soil is moist. After a good rain or watering is a great time to grab your favorite weeding tool, and enjoy the time, knowing you'll have instant gratification when you see the weed free patch. If water is scarce, then slicing the weeds just under the soil level will kill the surface portion. This is good for annual weeds, but several continuous applications will be necessary for perennial ones. Keep your weeding hoe nice and sharp to make the job easier.
4. Snap off their heads
If you can't remove the weeds completely, getting rid of the flowering parts will help. Especially with annual weeds, deadheading will help prevent the new crop of seeds from being distributed. Cutting back the tops of perennials reduces reseeding and uses up energy resources for next years growth.
5. Plant ground covers
Weeds seems to always find the open spaces. Planting ground covers to close up the gap between shrub and trees will eliminate these opportunities. Use mass plantings of your favorite plants or drifts of plants. But be careful to use recommended plant spaces for plants that need good air circulation. You don't want to freeze out weeds just to discover lack of air has resulted in plant disease.
6. Keep your soil healthy
Keep your eye on good soil management. Generally fewer weed seeds germinate in soil that contains fresh applications of good compost and organic matter.