Flowers that are especially suited for planting in strawberry jars are those that cascade, including petunia, lobelia, and impatiens.
For best effect, avoid using plants that will grow too large and hide the jar's interesting features. Keep the plants in the jar simple, using only a few plant types such as the New Guinea impatiens, sweet alyssum, zinnias, and wax begonias. Your strawberry jar can be instantly beautiful if you plant it with flowers in bloom or in bud. If you grow your annuals from seed, give them an early start indoors.
Pick flower colors that complement the red in the clay. For a cooling color contrast, poke such white-flowering favorites as candytuft, sweet alyssum, or begonias into the pockets. Blue or violet will burst into life from ageratum, nierembergia, or lobelia. One of the most cheerful combinations can come from pansies; their "faces" will peek in all directions from the jar.
Your choices also will depend on where the jar will be placed. In a cool, moist, and shaded spot, try baby-blue-eyes, browallia, or mimulus. Out in the sun, marigolds, zinnias, and petunias will do best. In areas where it's very hot, drought-tolerant portulaca or vinca are good performers.
1. Add soil. Fill the jar to the lowest pocket with moist potting medium that is light and crumbly but moisture-retentive.
2. Prune. To help plants adjust more readily if weather is not ideal at planting, clip off flowers. Plants will form new buds as soon as the roots establish themselves.
3. Add plants to pockets. Set one plant into each pocket, then add soil to cover the roots. Firm the soil gently. It's easiest if you start with the lowest pocket and work your way up the jar.
4. Finish. When all the side pockets are planted, plant in the top of the jar. Again, to ease the adjustment for plants, clip off flowers already in bloom.