The genus Viola, commonly known as violets, contains over 500 species widespread across the Northern Hemisphere. While recognized for their delicate, five-petaled flowers, the production and dispersal of their seeds are a crucial part of the violet’s life cycle. Understanding seed development and appearance is necessary for anyone looking to propagate these resilient plants.
Visual Characteristics of Violet Seeds
Violet seeds are notably small, typically measuring between one and three millimeters in length, making them easy to overlook. They usually possess an oval to slightly pear-shaped form, with a smooth, hard exterior. The color varies depending on the species and maturity, ranging from a pale tan or light brown to a dark, almost black, shiny finish.
A distinguishing feature is the elaiosome, a small, pale, fleshy attachment rich in lipids and proteins. This white or cream-colored appendage appears on one end of the seed. The elaiosome is not part of the seed itself but serves a specific purpose in dispersal. The overall size and color make the tiny seeds resemble miniature, polished pearls or dark grains of rice.
How Violets Develop Seed Capsules
Violets use a mixed reproductive strategy, producing two distinct types of flowers to ensure successful reproduction. The familiar, showy, open flowers are called chasmogamous, and they rely on insect pollination for cross-fertilization. However, the majority of violet seeds are produced by a second, less conspicuous flower type.
These are the cleistogamous flowers, which remain closed and self-pollinate without ever opening their petals. These flowers are often small, bud-like, and sometimes develop near the soil surface or even underground. The three-part seed capsule, or fruit, develops from the ovary of both flower types. It starts green and eventually dries out, turning brown as the seeds mature inside.
Natural Seed Dispersal and Collection
The small, three-valved seed capsule is designed for ballistic dispersal. As the capsule dries, the three sides constrict, creating tension until the fruit snaps open, mechanically launching the seeds several feet away. This action ensures the seeds do not simply drop directly beneath the parent plant.
A secondary dispersal method, called myrmecochory, involves the elaiosome. The fatty, oil-rich appendage attracts ants, which carry the seeds back to their nest to feed the elaiosome to their larvae. The ants discard the intact seed in their waste areas, where the protected environment aids in germination.
To collect seeds before they are launched, monitor the capsules as they stand upright and begin to turn pale or brown. Placing a fine mesh bag or a small container around the capsule once it has lifted its stem will capture the seeds when they are explosively dispersed.
Preparing Violet Seeds for Germination
Violet seeds exhibit deep dormancy and will not germinate immediately after collection. To successfully sprout them, the seeds require cold, moist stratification, which mimics the natural winter cycle. This treatment breaks the seed’s internal dormancy and prepares it for spring growth.
A common method is to mix the seeds with a damp medium, such as sand or vermiculite, and place the mixture inside a sealed plastic bag. Store the bag in a refrigerator at 33 to 41 degrees Fahrenheit for six to twelve weeks. Maintaining consistent moisture is important, as is checking for any premature sprouting. After this simulated winter, the seeds are ready to be sown.