Late-Summer Flowers: Annuals Extend the Bloom Season

Perennial borders often peak in May-July and fade by late July. Annuals are the key to color through early fall. Choose vase-shaped, old-fashioned annuals that weave among perennials: verbena, nicotiana, salvia, diascia, heliotrope. Pick heat-tolerant types: ageratum, alyssum, cleome, morning glory, browallia, nicotiana, salvia, verbena, matricaria. Don't neglect tropicals (canna, elephant ear, ginger lily, Mexican sage, plectranthus) for bold accents.

Plant annuals in spring into perennial borders; move flowering ones from cutting garden on rainy days to fill gaps. The author's favorites:

• Matricaria: white blast, grown from seed.
• Mums: treat as annuals, pinch until early July for fall blooms.
• Coleus: hundreds of colors, pinch for bushiness, remove flowers.
• Anise Hyssop: self-sows, good form, fluffy purple flowers Aug-Sept.
• Salvia horminium (viridis): showy bracts (purple/pink/white) last till late fall.
• Impatiens: pink, shade-tolerant, bloom till frost.
• Cleome: 4-ft plumes at border back, July-Sept.
• Ammi majus: airy Queen Anne's lace, sow June-July.
• Sanvitalia procumbens: mini black-eyed Susan, heat-loving, front of border.
• Salvia farinacea 'Victoria': stiff but good mid-border filler.