Summer bulbs

By Michele Koskinen  

White fragrant lilies and hardy gladiola

When you hear bulbs what is the first flower you see in your mind? Is it a tulip, daffodil, crocus, snowdrop or other fall planted bulb. Can you name your favorite summer bulb? Flowers planted in the spring from bulbs or corms or rhizomes are called "Summer Bulbs". These include begonia, caladium, canna, dahlias, gladiola, lilies of many varieties, oxalis, and many more. Some are tubers and others corms but for this discussion they are all grouped together as summer bulbs. 

crocosemia

Fragrant Oriental Lily

Growing conditions for summer bulbs are different from spring bulbs in that a summer bulb needs full sunshine, with some exceptions, and decent soil and excellent drainage  (if the soil is clay and drainage is poor, the bulbs will rot). If those 3 conditions are met, it will most certainly give the summer bulbs a good growing habitat. Spring flowering bulbs will thrive in poor and infertile soil and extreme conditions of heat and cold. Summer bulbs need their requirements met to thrive. 

To get off to a good start, the bulbs need consistently warm soil. The planting date should always be after the last frost and the temperature preferably between 50 and 60 degree. 

                                                

Dahlia

 Many summer flowering bulbs and tubers are well suited for patio containers and should be planted closer for a full look. The most popular are begonia, dwarf canna, caladium and dwarf dahlia. 

Caladium and begonia

dahlia

Summer bulbs also require winter storage in a cool dry place after being dug up for the winter. Most of the tender bulbs require 40 to 50 degree temps in dry vermiculite or peat moss. Some grown in containers can be moved indoors and left in the pots to 
overwinter. A too warm storage climate dries them out and they are not viable the next season. 


Many summer bulbs are considered  hardy in our zone 6B-7 and do not need to be lifted. Iris and lilies are two that can be left in the ground and will multiply through the years as a regular perennial. For more information on the hardiness of the bulb, read the growing directions for the specific bulb you are planting.

A few tips from professionals.

Summer bulbs require a great deal of water immediately after planting. 

The soil in your garden should be continually moist not wet.

Sprouting is healthy; plants are anxious to get into the ground again. 
Maintain a pH level of 6 to 7 to bring out the true color of flower bulbs. 
Additional fertilizer is not necessary for summer flowering bulbs and tubers.