Do Nasturtiums Have Oxalates?

Types of Oxalates

• Not all oxalates are created equal. Nasturtiums contain oxalate acid, which if consumed in large enough qualities can irritate the stomach and even cause kidney problems, according to Hampshire College; however, these issues are most often seen in pets such as parrots or reptiles that are given large quantities of nasturtiums by unsuspecting owners. The ASPCA lists nasturtium has non-toxic to cats, dogs and horses. "Mother Earth News" provides tasty recipes for using the leaves and flowers. Don't confuse the oxalate acid in nasturtiums with the non-soluble calcium or potassium oxalates with their tiny crystals that can severely irritate soft tissues and that are highly toxic. Soluble calcium oxalates, however, are present in some garden foods, but in large enough amounts can sicken or kill a pet or person.

Nasturiums in the Kitchen

• Nasturtiums are well-known for their edible properties. The stems and leaves have a stronger taste than the blooms, but all three are edible. The reason they are safe to eat is because they are not usually consumed in large quantities. They are usually used to decorate pastries, salads and to flavor soups, and this is not nearly enough to cause harm. A wheelbarrow full of the plants, however, is enough to kill a pig, according to Hampshire College.

Nasturtiums in the Garden

• Nasturtiums are usually grown as annuals, but they can also be grown as tender perennials in U.S. Department of Agriculture plant hardiness zones 9 through 11. They thrive in sandy soils in full sun or light shade. Although drought tolerant, they grow best when the soil is kept barely moist and in areas with warm daytime temperatures followed by cool nights. Nasturtiums do not tolerate hard freezes and may stop blooming during very hot weather.

Nasturtiums and Children

• Nasturtiums are an ideal way to introduce children to gardening. The seeds are large and easy to handle, and the plants grow fast enough to provide gratification to even the youngest gardener. Several cultivars are available, including plants that grow in bushy forms and plants that will twine up a trellis or other support structure. They will also trail attractively over the edges of a hanging basket.