Plants are remarkable organisms. They have adapted to life in almost every corner of the Earth over thousands of years and many have done so through storing food reserves underground. Here are the five main methods plants store excess food underground.
Bulbs are technically very short stems with the growing tip enclosed by thick, fleshly, scaly leaves. Typically these are thin and packed closely together. A common example of a bulb is the daffodil. Bulbs that flower in the spring are typically planted in the fall while bulbs that flower in the summer and fall are typically planted in the spring.
Corms are similar to bulbs and can be easy to confuse. The main difference is that bulbs have fleshy scales while corms are solid structures. Corms also have shorter lifespans and are typically replaced by new corms that form on top of the old one as the plant matures and food stores continue to get pushed to the underground base of the plant stem. Common examples of corms are gladioli and crocosmias.
Tubers are the swollen and enlarged fleshy ends of an underground stem. The most common edible tubers we see are potatoes, sweet potatoes, and sunchokes. Tubers can be divided into root tubers and stem tubers. Root tubers do not have any nodes or eyes while stem tubers have “eyes” that can be sprouted when germination conditions are right.
Rhizomes are plant stems that grow horizontally on or just below the soil surface. Rhizomes often appear to be segmented into notes, and this where new leaves, shoots, and roots develop. Thye can also be separated into pieces and as long as there is a growing point, a new plant can be propagated. Common rhizomes include ginger and ferns.
Stolons are similar to rhizomes in having horizontal stems, but they differ as they are not the main stem of plant. When stolons are produced above ground, they are referred to as runners (ex. strawberries). New plants can be propagated from the end of each stolon. A common edible plant that produces stolons is mint.
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