“Jup was not forgotten, and he ate with relish some stonepine almonds and rhizome roots, with which he was abundantly supplied.”
"The Mysterious Island," by Jules Verne
Imagine strolling through the garden just after sunset on a warm summer night and the moonlight shines on bright white lilies. You notice their amazing fragrance filling the air with a touch of romance. As you stroll, you admire giant stalks of gladiola blooms that shoot upward as if they were rocket ships headed toward the moon. Tall ornamental onions burst with fireworks of color in the night sky. These are a few common summer bulbs which can transform an otherwise ordinary flower garden into a magical space. Summer bulbs can create a more natural look to a garden and with careful planning, site preparation, tending and maintenance, they can also prevent weeds from taking over the garden. The night blooming summer bulbs are not only romantic, but they serve another purpose, attracting nighttime pollinators.
Plan and Site Preparation
Look for plump, firm bulbs when selecting for planting. Their growing points should be well formed and not damaged. Choices like Allium and lily are hardy and can overwinter in colder climates. Plant them in the fall for blooms the following summer. More tender summer bulbs like gladioli, cannas, and dahlias are best planted in the spring and dug up in the fall for storing in the winter indoors. You will generally find them available for sale or if buying from a catalog, shipped to you at the appropriate time for planting.
Larger bulbs are best used for more ornamental beds in clusters and mixed in with other perennials. For naturalizing an area of your garden to make it look like a meadow or woodland floor, smaller flowering bulbs or native bulbs are your best choice for planting. They can be propagated by seed or purchased by bulb at a native plant nursery in Washington.
Most summer bulbs require well drained soil and do well in open, sunny habitats. Many native bulbs can tolerate more shade and moist soil conditions. For sun lovers select a site that has at least 5 to 6 hours of direct sunlight. If you want to overwinter bulbs in the soil you will need to ensure 8 to 10 hours of sun. In soils that stay wet during the winter it is often a good plan to dig them out after they have died back in the fall and store them for the winter. To naturalize an area, toss the bulbs and plant where they fall to create a scattered effect. When flowering bulbs fill in a bed they will help keep weeds under control. As a general rule of thumb, bulbs should be planted 3 times the diameter of the bulb in depth.
Night & Day Pollinators
Night bloomers such as the ‘Casablanca’ lily and gladiolas are great nighttime pollinator attractors. Bats and other nighttime feeders like moths will collect nectar from the large flowers while brushing themselves against the pollen and stigmas.
Daytime pollinators like hummingbirds, butterflies, and bumble bees are attracted to flowering bulbs because of their large blooms which contain lots of nectar and pollen and are easy to access.
Types of Summer Bulbs
?Bulbils are small bulblike structures at the base of a stem or axil of a leaf and can form a new plant, some lilies, onions, and garlic create bulbils.
?Scales are parts of the bulb that can be peeled off like an onion and planted separately to create a new plant, lilies have scales.
?Rhizomes are part of the stem that grows underground creating adventitious roots and shoots for a new plant. Ginger and Iris have rhizomes.
?Tubers are fleshy stems that store nutrients to produce shoots and leaves of new plants. Begonias begin from tubers.
?Corms and Bulbs are considered true bulbs with layers of modified leaves. These include flowering onions and lilies.
Caring for Your Bulbs
Mulching plants is a great way to preserve water while keeping weeds down in your garden beds. Summer bulbs appreciate the even soil temperature mulch provides too. Apply mulch such as straw, pine bark, hay or leaves in early spring to conserve water and keep weeds down and in late fall for areas where bulbs will be overwintering.
During spring, water from rain is generally enough for bulbs. When hot, dry weather arrives in July and August, a thorough soaking of the ground is helpful at weekly intervals; be sure to water even after blooms are done flowering.
High-nitrogen fertilizers are not good for flowering bulbs, use a lower nitrogen organic fertilizer instead of chemical based ones. Bone meal is a good supplement as an extra source of phosphorous; this helps create larger blooms and keeps them blooming for a longer time.
Don’t forget to stake larger, taller flowering bulbs to prevent top heavy blooms from falling and breaking at the base. If you leave your bulbs in the ground over the winter, leave their leaves to grow on the plant for up to 6 weeks after the last bloom. The leaves produce food the bulbs need to store energy for the new plant next year. Sometimes bulbs can get overcrowded in the garden bed. This is a good time to dig them up and separate the bulbs into smaller sections, do this in the fall after removing the dying foliage so blooms are not compromised for the following year.
Storing Tender Bulbs
?Gently lift the bulb out of the soil using a garden fork.
?Clean the bulb and roots by brushing off excess soil.
?Dry bulbs on a paper towel or newspaper in a sheltered location for a couple of days.
?Place the bulbs in a paper bag or box and set them in a cool, dark place such as garage, basement or vegetable crisper.
Some common animals that damage bulbs include squirrels, mice, and voles. Protect your bulbs from these digging critters by placing a layer of chicken wire over your bulbs in the soil then covering it with soil. For voles, a small box-cage of chicken wire created around the bulbs will prevent the voles from coming up from underground and eating them.
Watch out for summer insects that feed on your plants – in more recent years the red Lily Leaf Beetle (Lilioceris lilii) has become a concern for summer bulb growers in Western Washington. Laying up to 450 eggs per season these pests feed on the undersides of primarily lily leaves and can move to stems and flowers as well. Check your plants often, especially the undersides of the leaves where they feed. Handpick them off your plants – look for their eggs too to prevent a generation! For more information check this WSU bulletin. Keep an eye out for aphids too. Aphids are notorious for infesting the robust, growing buds of summer bulbs. Wash them off with a strong jet of water, being careful to hold the bloom steady so you don’t knock it over. Slugs and snails can keep bulbs from growing in the spring – chomping down any little growth that emerges from the soil. Set out baking yeast and water or beer filled traps around your plants to dissuade them from eating your bulbs. Once the trap is full, dump it and fill it up again.
Native Summer Bulbs – Good for Naturalizing
Harvest Lily (Brodiaea sp.); native to open, dry, rocky sites and grassy meadows of the Pacific Northwest.
Onion (Allium sp.) with 30 species, these bulbs have grass-like leaves and a garlic-like odor. They are found in the wild in open forest, dry hills and flats, dry rocky knolls and coastal headlands of the Pacific Northwest.
Camas, Indian Hyacinths (Camassia quamash); the most important “root” foods of western North American indigenous people. Grows on grassy slopes and in meadows.
Bellingham Lily is a native Northwestern lily with a parent from the San Juan lily. https://garden.org/plants/view/172545/Lily-Lilium-Bellingham-Hybrids/
Ornamental Summer Bulbs
Abyssinian gladiolus (Acidenthera bicolor)
Angels’s Fishing Rod, Wandflower (Dierama) – can reseed easily / trim flowers after they fade.
Butterfly ginger (Hedychium coronarium) - edible tubers!
Calla Lily (Zantedeschia aethiopica)
Dahlias – edible flowers!
Elephant Ear, (Colocasoa esculenta)
Gladiolas bysantinus, papilio, & nanus (Gladiolus)
Iris, Bearded iris
Jack-in-the-Pulpit (Arisaema candidissimum)
Montbretia (Crocosmia) – pollen can be gathered as a substitute for saffron
Mexican Tiger Flower (Tigridia pavonia)
Oxalis (Oxalis regnellii)
Southern Bugle Lily (Watsonia)
Tuberous Begonias (Begonias)
Voodoo Lily (Dracunculus vulgaris)
For more information about summer bulbs and how to grow them naturally, please contact the Garden Hotline at 206-633-0224 or www.gardenhotline.org. You can also find us on Facebook, Twitter, Pinterest and YouTube.