If you think you don't have room to garden, consider planting in tight spots such as the cracks of patios and walkways or the pockets of unmortared walls, which are ideal for some plants. Any pocket and chink that you can fit a trowel or even tablespoon into can be planted. Remember that with vertical spaces, such as a stone wall, the plants may eventually hang down a few feet so don't set other plants directly below or they may be smothered. In traffic areas, such as patios and pathways, stick to sturdy compact plants such as creeping thyme.

Planting Seeds Vertically
Starting plants in vertical spaces can be tricky because seeds and soil often wash out. Try the technique below.

1. Fold an index card in half lengthwise and sprinkle seeds from a packet into the folded card.

2. Position the seed-filled card in the crack to be planted, then blow the seeds into a fine, rich soil mix in the crevice.

3. Mist the seeds with a spray bottle of water, apply a piece of facial tissue to the dampened crevice to act as biodegradable mulch, and mist regularly while the seeds germinate and become established.

Plants for Cracks and Crevices
Look for small-scale and mat-forming plants that tolerate dry conditions for small, rocky spaces. Some good choices are listed below.

Alpine lady's mantle (Alchemilla alpina), a mat-forming perennial with tiny chartreuse flowers for Zones 3 to 7.

Corsican sandwort (Arenaria balearica), an evergreen perennial ground cover with white flowers for Zones 4 to 7.

Snow in summer (Cerastium tomentosum), white-flowered mat-forming perennial with silvery leaves for Zones 3 to 7.

Corydalis lutea, a long-blooming perennial with yellow blooms for Zones 5 to 8.

Pinks (Dianthus), especially cushion- or mat-forming rock-garden pinks, which bloom in a range of colors; hardiness varies.

Creeping baby's breath (Gypsophila repens), a mat-forming, semievergreen perennial with white, pink, or purple flowers for Zones 4 to 7.

Curry plant (Helichrysum italicum), a small, shrubby perennial with silvery to yellow foliage and yellow flowers for Zones 7 to 10.

Corsican mint (Mentha requienii), an aromatic, mat-forming perennial with lilac flowers for Zones 6 to 9.

Moss phlox (Phlox subulata), an evergreen creeping phlox that blooms in pink, purple, red, or white, for Zones 3-8.

Saxafrage (Saxifraga), a genus of mat- and cushion-forming flowering perennials ideal for rock gardens; hardiness varies.

Stonecrop (Sedum), a large genus of highly variable succulents ranging from very cold-hardy perennials to tender houseplants.

Houseleeks (Sempervivum), a genus of mat-forming succulents that form characteristic rosettes; hardiness varies.

Creeping thyme (Thymus serpyllum), a low-growing perennial with aromatic foliage and white, pink, or red flowers, for Zones 4 to 9.

Violets (Viola), especially spreading perennials or reliable self-sowers suitable for rock gardens; hardiness varies.