Choosing a color scheme is a good way to start when you want to design a garden mosaic. Mosaic art for the garden or yard can certainly be colorful, as that is the point, but as mosaics are made up of many small, broken tiles or dishware pieces, a mishmash of colors used at random may make the finished look appear tacky. Picking objects to apply mosaic patterns to should be done with a lot of creativity on your part, as almost anything, such as plant pots, stepping stones and tabletops, can be finished in this craft form. Having both the base objects and tile or dish pieces in front of you to reflect on may inspire you to come up with creative design ideas.
Secondhand stores, garage sales and flea markets can be great sources for inexpensive dishware that you can break to design your garden mosaic. Tile manufacturers often sell tiles with imperfections at a big discount, so these can be ideal for breaking up to use for a garden mosaic. Sometimes, the color of a tile or dish may inspire you to have a certain idea, such as greens for leaves or stems and yellow for flowers or a butterfly. By creating a section at the bottom of your garden project such as a grassy field of flowers, then adding another portion of sky, but with butterflies or birds or clouds for detail, you can create a pictorial mosaic. It's crucial to stick to a mix of one color for each part, or the piece is likely to look overdone and gaudy.
Instead, by using all one color, but different shades and patterns of the color, for each object in your mosaic picture, you can create depth and artistic interest. As an alternative to a picture type of garden mosaic, you could create a symmetrical design using a border and a center detail. For instance, on square pieces of concrete you are using for stepping stones in your garden, you could use various shades and patterns in a lighter main color for the background. A collection of darker broken dishware or tile pieces in a darker color could then form a contrasting border around the edge as well as a detail in the middle such as a heart or other shape. The same idea could be used to create a garden mosaic table.