Water Violet (Hottonia palustris):Water violet, the remedy for those who feel cut off from others, is made by the sun method.
Hottonia palustris or water violet has finely divided leaves and is sometimes known as featherfoil or water yarrow. Lineaus named the genus after a Dutch professor of medicine and botany at Leiden University, Petrus Hotton (1648 – 1709). There are only 2 species in this genus – Hottonia palustris, native to Europe and Western Asia and Hottonia inflata, native to North America. The American species has markedly smaller flowers but thicker stems.
Water violet is an aquatic plant with submerged leaves. This has implications for its chemical defences. Phenolic compounds form an important part of many plants’ defences. A study of the total phenolic content of 40 aquatic and semi-aquatic plants with floating, emergent of submerged leaves found that the total content was least in submerged leaves.Phenolics, including tannins, offer protection against pathogens, herbivores and UV-B radiation. Floating or emergent leaves are more vulnerable to attack as they are accessible to pathogens and herbivores in and out of the water. Submerged leaves have a lower nitrogen content and a lower calorific value, making them less attractive to herbivores. Also, as UV-B light penetrates water poorly, submerged leaves have less need for protection from it.
In fact, the presence of both light and carbon dioxide are required for the synthesis of phenolics and other compounds in plants and both of these components are in limited supply beneath the water. To enable submerged leaves to obtain enough to provide energy, the leaves are thinner (so have a larger surface area to volume) and lack cuticles, so are relatively simple compared to floating or emergent leaves.
Aquatic plants can still obtain enough light to carry out photosynthesis, even when they have submerged leaves. However, suspended particles, dissolved substances and water depth can restrict the amount of light that penetrates the water. As in non-aquatic plants, the light is harvested by chlorophyll in the leaves, providing energy to convert water and carbon dioxide to glucose and oxygen. Water violets are termed oxygenating plants which get their nutrients from the water and also release oxygen back into the water. Therefore, they help maintain the ecological balance and prevent overgrowth of algae.
The plants are an important source of oxygen for fish and invertebrates living in the water and if the quantity of light available is compromised (e.g. by cloudy weather or the introduction of certain light blockers into the water) these may not survive.
Water violets are vulnerable to the removal of their preferred habitat e.g. by increased urbanisation and in some places, e.g. Germany, they are considered to be endangered. Other potential threats include water contamination and/or overgrowth of algae or other plants. Bodies of water are sometimes treated with herbicides to remove unwanted growth, but these can also affect non-target plants, such as water violets.
Water violets flower in May and June, producing white or pale violet flowers with yellow ‘eyes’ which are held above the water.For an introduction or sources and more info., click the links.