Hibiscus Mite

Bumpy, wart- like growths on hibiscus leaves. 

This unsightly growth is caused by the feeding of a tiny mite, invisible to the naked eye, called the hibiscus erineum mite.  It has been in the Hawaiian Islands since 1989 and is carried from place to place by wind, birds and insects.

The mite is difficult to eradicate, and even when it is gone, it will likely return.  Biological control is the best long-term solution.  Soon after the mite becomes established, a predatory mite will most likely move in and begin feeding of the erineum mite. 

Since the predatory mite will only reduce the pest population and not eliminate it, there will continue to be some damage. If not satisfied with biological control, using a chemical spray would be the next step:  1) prune to eliminate the worst damage, 2) spray with a registered miticide; wettable sulfur.  3) Apply 2-3 times, at weekly intervals, paying special attention to spraying the undersides of the leaves.  In addition to killing the mites, the spray will protect the new growth from further infestation so gradually the shrub will begin to recover. 

Unfortunately, a miticide application will also kill the predatory mites, so it is either biological control or chemical.  If you see tiny, fast moving mites on the leaves, these are the predatory mites. You may want to give them a chance before pesticide applications.

Research conducted at CTAHR’s Kahului Experimental Station (Maui) indicates that some hibiscus varieties are more susceptible to this mite than others.   The more susceptible varieties are:  Chinese Red, Herman Shierman, Orange Hibiscus, Nii Yellow and Kardinal.  Those varieties that show a lesser susceptibility to the mite are: Itsy Bitsy Peach, Monch, Zahm, Apple blossom, Apricot, Empire and Pink hibiscus.  

Tropical Favorites

Some favorite tropical fruits, spices and flowers all belong to the same plant order known as the Zingiberales. They include banana, ginger, cardamom, turmeric and the beautiful heliconia flowers.

Banana, sometimes referred to as a tree or palm, is actually an herbaceous plant since the trunk or stems do not contain lignin. Lignin is the substance that makes wood, woody.  

Ginger originates from Southeast Asia and is unknown in the wild but has been cultivated since ancient times. Ginger was introduced into Europe from China and introduced into Mexico and the Caribbean by the Spaniards. Today it is widely used in local medicines in India and the Far East. China and India are the largest producers of ginger.   

Cardamom is native to India. The dried fruits are used in medicine and as a spice.  Cardamom seeds, which have a pleasant aroma, are used in curries and breads.   

Turmeric, or olena as it is called in the Hawaiian language, comes from the root of Curcuma domestica; it is an important ingredient in curry powders.  Turmeric has been gaining recognition as an anti-inflammatory herbal remedy. Preliminary findings suggest that a chemical found in turmeric called curcumin may have carcinogenic retarding properties but these findings have not been confirmed. With its bright yellow color, turmeric is also used as a fabric dye. This species is unknown in the wild; it is sterile and does not produce fruit. Turmeric is also known as Indian saffron. 

Lastly, in the plant order Zingiberales there are over 100 different species of heliconia flowers.  They produce some of the most beautiful and commercially important flowers for both potted plants and bouquets. Heliconias require high temperatures, humidity and light intensity.  In the wild they grow mainly in forest clearings. The Bird of Paradise, which is the national flower of South Africa, is also in this group. 

Edible Ornamental Plants

In frontier times, people foraged the  nearby hills and fields for edible plants. Since the early 1900’s, however, Americans began the great migration to the cities and  eventually lost their foraging ability. Perhaps the time has now come to learn which ornamental plants and common weeds can be a  good source of nutritious food.

Here is a short list of some well-known edibles. Many university websites have a more comprehensive list of ornamental edibles.

A. Weeds - If you can’t beat them, eat them!

 1. Dandelions, Taraxacum officinale -Fresh dandelion leaves can be eaten raw, in salads, added to a stir fry, or boiled and steamed like spinach. They have a bitter taste, but boiling will help take that out. Dandelions also make a great addition to soups and stew. They are high in carotenes, iron, calcium and vitamins A and C. As a detoxifying agent, dandelions aid with liver, urinary and gall bladder disorders, diabetes and high blood pressure. Dandelion root tea is sold in local health food stores. 

2. Lamb’s quarters (Chenopodium album) is also called wild spinach with similar nutritional value to spinach. 

3. Burdock (Arctium Lappa) is a weed rich in potassium, iron and calcium. 

4. Common mallow (Malva neglecta) the leaves, stems, and immature seeds are eaten raw or cooked. Mallow is reported to be rich in calcium, magnesium, potassium, iron, selenium, and vitamins A and C.

 5. Purslane (Portulaca oleracea) is a succulent; the leaves, stems and flowers can be eaten either fresh or cooked. The leaves contain more omega-3 fatty acids than any other leafy vegetable plant.

Other edible weeds include chickweed, white and red clovers and plantain.

B. Edible Flowers

1. Marigolds are one of the most commonly grown ornamental annuals. When dried and crumbled, the petals of marigolds can substitute for the most expensive spice in the world: saffron. 

2. Roses, both the petals and the rosehips (fruit), are edible. Rose water is often used in scones, cakes, sherbets, salads and icings.  

 3. Sunflowers – in addition to the commonly eaten seeds, the petals can be added to soups and stir-fry dishes. The sunflower buds can be steamed and eaten like an artichoke.

4. Daylilies (Hemerocallis sp.) - Some species (especially H. fulva) are cultivated in Asia for their edible flowers. The petals can be eaten raw or more commonly dried and used as a flavoring in soups. The young shoots should be cooked and have a pleasant sweet flavor. Even the roots are edible.

Nasturtium, violas, borage and calendula flowers are also edible and frequently used in salads.  Bon Appetit! 

Caution: Before collecting, research the plant to verify it is edible, and more importantly, make sure it is properly identified. Eating the wrong plant can be disastrous.