Check the cuttings after three weeks, gently pulling the stems to see if roots have formed. Resistance indicates the growth of roots, and the plastic bag can be removed at this point. Keep the soil moist and feed only if new green growth appears, using a fertilizer with low numbers. Cuttings started in late spring should have sufficient roots to plant in the garden by the end of summer. If cuttings grow rapidly, you can separate and replant them in individual pots until it's time to plant them in the garden. Don't pinch plants to induce side growth until the second year.
Shrubs and trees to root from softwood cuttings include barberry (Berberis spp.), beauty bush (Kolkwitzia spp.), butterfly bush (Buddleia spp.), clematis, cotoneaster, crab apple (Malus spp.), deutzia, dogwood (Cornus spp.), forsythia, honeysuckle (Lonicera spp.), maple (Acer spp.), lilac (Syringa spp.), magnolia, maidenhair tree (Ginkgo biloba), Russian olive (Elaeagnus angustifolia), privet (Ligustrum spp.), rhododendron, rose, summersweet (Clethra spp.), weigela, willow (Salix spp.), wintercreeper (Euonymus spp.) and wisteria. Many other woody plants can be propagated by softwood cuttings, so experiment with other species in your garden.
Many herbaceous perennials can be propagated from softwood cuttings, too. Follow the above steps for propagating shrubs, only make the cuttings shorter—four to eight inches (10 to 20 centimetres) long.
Try artemisia, baby's-breath (Gypsophila spp.), blanket flower (Gaillardia spp.), bleeding-heart (Dicentra spp.), butterfly weed (Asclepias spp.) campanula, chrysanthemum, coral bells (Heuchera spp.), delphinium, lavender, pinks (Dianthus spp.), speedwell (Veronica spp.), spotted deadnettle (Lamium spp.) and evening primrose (Oenothera spp.).
Groundcovers include periwinkle (Vinca spp.), pachysandra and Boston ivy (Parthenocissus tricuspidata). Geraniums (Pelargonium spp.), actually tender perennials, root easily from cuttings. However, geranium cuttings require less humidity; don't enclose them in a plastic bag.