when you are faced with your first web-site, and you have made a reasonable start - at least you have the page on the web.
It's not possible to provide a complete tutorial here, but I can provide a few comments.
1. Consider carefully when selecting backgrounds and text combinations - you want the text to dominate, not the background. Nowadays there's a tendency towards white backgrounds with images and text displayed to best advantage, and I normally advocate that approach, but............... in your particular case I think there's every reason to go to town with some colour and texture - garden services make one think of green foliage and flowers. You'll find lots of appropriate copyright images on the web, and you should experiment. I would prefer to see an image of a colourful garden than a picture (however good) of a JCB.
2. Your page title needs revising. C.W GARDEN SERVICES in grass green with the COTTINGHAM EAST YORKSHIRE part in say, a dark chocolate brown would look pretty good. The second line should also be in a smaller font size.
3. You need more than one page if you want your business to look something on the web. I'm sure you can come up with a second page, giving a more detailed description of your services, with perhaps contact details. You can add the odd image or two as well. Close-up pictures of flowers, or even a few tools leaning against an old wooden shed would add atmosphere.
4. Take a look through some magazines and gardening books to see how images can create atmosphere. The one thing that sells your kind of service is atmospheric images - people like to daydream, and to see what's possible.
Come back for more advice, and technical help when you need it. What software are you using to design the site by the way?