The early summer garden is a cheerful place, filled with bright bulbs, long-awaited perennials and promising greenery. As some early flowering bulbs and perennials fade and die back, gardeners may be left with spots in their garden or pots to fill. Annuals are a worthy solution and offer more variety than many gardeners in the New York area explore. Here are a few candidates you may not have tried or that are available in expanding varieties that are worthy of consideration.
Snapdragons (Antirrhinum) are a terrific addition to an early-season, annual display but, unfortunately, once the heat of the summer sun is upon us they tend to fade quite quickly. An easy solution to recapture the look of elegant vertical spires covered with blossoms is to swap them out with summer snapdragons (Angelonia).
Interesting cultivars include the cascading Angelonia 'CaritaTM Cascade Raspberry'. It reaches only 8 to 10 inches tall, yet spills over to form a 20 inch cascading mound. It doesn't require any deadheading and, like other summer snapdragons, it is deer resistant and heat and drought tolerant. This is the ideal candidate for spilling over the edge of a container or at the front of a border. It would partner beautifully with a dark leaved coral bell (Heuchera). For a less tumbling appearance, consider Angelonia 'SerenaTM Lavender Pink'. It gets 10 to 12 inches tall and just as wide, quickly filling out in the garden and forming an appealing clump. The lavender-pink color of the blossom will blend with just about anything. This cheerful annual looks genteel with the silvery foliage of a trailing licorice plant (Helichrysum petiolare) and white fan flower (Scaevola 'Bombay White').
The Angelonia AngelFace® and AngelMistTM series offer more substantial plants that can be placed further back in a border. These summer snapdragons can grow to be 18 to 24 inches tall and fill out beautifully over the course of the summer. Pair the bi-colored (purple and white) 'AngelFace® Wedgewood Blue' with an apricot nasturtium (Tropaeolum 'Tip Top Apricot') for a beautiful display.
While these summer snapdragons are advertised as needing no deadheading, most do benefit from occasional deadheading which cleans them up and encourages more new growth. They will grow and flower profusely regardless. While they can handle drought, they also grow well in average garden soil. This is an easy, no fuss annual that performs consistently all season long.
African lily, or Agapanthus, is hardy only from zones 7 or 8 to 10, so not in the New York area. The good news for those of us living outside the hardiness zone is that Agapanthus love to grow in a pot and don't mind crowded quarters. In this part of the country, the easiest thing to do in winter is to store the containers in a cold basement or garage, and keep the plants from drying out. African lilies look like ornamental onions and then again they look like lilies; they have wandered between these classifications over the years. Its fleshy roots are rhizomes and it is often sold as a bulb in catalogs. It is also available potted at the nursery in the summer.
This African beauty comes in all sizes. The dwarf varieties hold their globe-shaped flower two feet above their strap-shaped foliage. The flowers on taller varieties float up to five feet above the foliage on long, erect stems. Like ornamental onions, the shape and form of the African lily flower, while technically an umbel, falls into the lollipop category, making them wonderful accents or focal specimens.
The color of the flower is heavenly, ranging from white to intense, dark blue, with all shades of lavender in between. Agapanthus flowers from midsummer into October and love full sun. An attractive hybrid with dark blue flowers that we have featured in containers at NYBG is Agapanthus 'Storm Cloud'. It grows very tall, boasting dark, 3 to 4 foot flower stems with dense umbels of up to 100 tiny flowers.
Agapanthus, like many garden denizens, thrives in well drained soil that is rich in organic matter. Water consistently throughout the summer for healthy plants and watch them grow!
Now for a plant that you certainly know well but perhaps not in all its varieties and uses. Marigolds are ubiquitous. You can find them at every garden center almost all summer long and like magic add instant color to your border or vegetable garden.
Companion planting practitioners extol the virtues of marigolds, suggesting that they deter aphids, thrips, whiteflies, Mexican bean beetles, squash bugs and tomato hornworms. Some marigolds are believed to deter nematodes that can attack tomato plants.
The name marigold is shared by two genera: Tagetes and Calendula. The first (Tagetes) is the marigold that we are more familiar with. These marigolds are indigenous to the Southwestern United States, Mexico and South America and are generally broken down into a few types.
Tagetes erecta are the tall marigolds that are commonly referred to as either African or American marigolds. Tagetes patula, while being native to Central and South America, were predominately hybridized in France and are thus known as French marigolds. They range in size from dwarf cultivars, 5 to 10 inches tall, to larger varieties that reach 12 to 18 inches tall. When you think of a stinky yet floriferous marigold, this is the one that you are picturing. Hybrids of Tagetes erecta and Tagetes patula are starting to flood the market. These sterile hybrids are sometimes referred to as mule marigolds, triploid cultivars or New World marigolds. They combine the best of both parents, producing robust flowers on 12 to 18 inch plants. The catch is that they are not as easy to grow as their parents.
Two lesser known cousins are edible. Tagetes tenuifolia (syn. signata) is called the signet marigold. Unlike its oddly smelly relatives, this one has an appealing fragrance. Its fine, feathery foliage has a lemony scent. The flowers of the signet marigold are edible and can be tossed in a salad or mixed into a dessert sauce. Tagetes lucida is commonly known as either the Mexican mint marigold or as Spanish tarragon. As the name suggests, it has a sweet licorice flavor that is reminiscent of tarragon. The flowers are used in salads and teas and the leaves are used as a substitute for tarragon, particularly in warmer climates where French tarragon will not grow. Careful though: in large quantities it can cause you to hallucinate.
Calendula, or the pot marigold, originated in the Mediterranean region. It does not boast the same pest repellent properties of its namesake but the pot marigold possesses some wonderful medicinal properties. It is used in ointments to repair damaged skin. The sap from the plant is said to remove calluses and warts. It has anti-inflammatory and antiseptic properties. It is also one of the tastiest edible flowers around. You will often find the thin petals strewn in high end salad mixes to add a spicy flavor.
Annuals for Every Garden by 
The Gardener's Practical Guide to Annuals, Bulbs and Perennials by 
Annuals and Tender Plants for North American Gardens by 
Agapanthus for Gardeners by 
Culinary Herbs for Short-Season Gardeners by 
The Well-Designed Mixed Garden by 
