Nasturtium is an annual plant with attractive flowers and unique looking lily pad-like leaves. It’s easy to grow and totally safe around children. Leaves and flowers are both edible.
Nasturtiums thrive in sunny locations on infertile soil. Strangely enough, high fertility yields fewer blooms. These flowers range in color from yellow, through orange and peach hues all the way to bright red.
Five petaled flowers are about two inches across and have a prominent structure called a nectar spur. This structure looks something like the similar structure on columbine and also resembles the bracts on impatiens. Leaves are either solid green or variegated.
These brightly colored flowering plants can be started indoors or simply planted from seed. I prefer to do that. The seeds are relatively large for annual flower seeds. They are about the size of chickpeas and look like little brains.
Plant them about an inch deep when soil temperatures are above 50 F. In less than two weeks little nasturtium plants will pop up and quickly fill the area. Thin them if necessary.
Plants grow well in sandy infertile soils, but they must be kept from drying out. A little added organic matter can improve their health. Some watering is usually necessary but don’t over water them.
When your stand of nasturtiums thickens you may begin to harvest flowers and foliage for salads. A little extra water at this time can be helpful. Nasturtium flowers and foliage have a slight peppery taste which is made stronger by water stress. Removing flowers will also keep plants flowering longer.
Nasturtium flowers add flavor as well as make a colorful garnish. Leaves are often used cooked as well as in salads. Both, especially the flowers, make a spicy herbal tea.
Numerous sources claim nasturtiums repel whiteflies, squash bugs, cucumber beetles and striped pumpkin beetles. I remember my grandfather always planted them in his vegetable garden. He always grew bountiful crops of cucumber and squash on that sandy Maine glacial till.
Another thing I do remember is that aphids and slugs often attacked them. For that reason some people plant nasturtiums as companion plants to lure pests from other crops. I’m not entirely sold on that.
Therefore, when growing nasturtiums to eat, they should be washed thoroughly. Eating aphids won’t hurt you but I have no desire to consume them. I worked with a graduate student who put aphids on peanut butter sandwiches and it nearly made me sick. He thought it was funny, but I managed to convince him not to do it in my presence again.
Herbalists have long touted this plant for its medicinal uses. It has strong antimicrobial properties and has been used for urinary tract infections. It also has been used to treat cuts and abrasions for bacterial infections. Nutritionally, leaves and flowers are good sources for vitamins A, C and D.
Whether you want to eat them, use them medicinally, employ them as pest repellants for your garden or simply enjoy their uniqueness and beauty, Nasturtiums have something for everyone.
Ted Manzer teaches agriculture at Northeastern High School (tmanzer@ecpps.k12.nc.us).