Posted: 14/05/2016 at 09:12
If you mulch (google it!) the borders it will not only help to improve the soil structure and keep moisture in so you don't need to water so much, mulch will also suppress weeds. Another good way of keep weeds down is to try and pack your borders out with plants so weeds can't get in edgeways. If you want to fill borders cheaply, go for plants that will wander freely, such as Geranium, or Vinca Minor (aka Periwinkle), both of which provide ground cover and then you can plant amongst it. Never let weeds flower - you don't want more seed dispersed into the gardens. Hoeing is also good, and to do it on a nice hot sunny day. You breaks up the top few inches of the soil and it looses it up so weeds lose their foothold, and expose roots to the air, which will kill them off.
Sorry to hear about your lawn - sounds like a duff job. You need to get them back in to review their work. What they've done doesn't sound like good job or good turf. Any reputable supplier would not have weeds growing in their turf.