Sunday, March 3, 2019

Medicinal Teas of Hawaii: Mamaki and Ko’oko’olau



Mamaki (Pipturus albidus)  is a Hawaiian endemic plant occurring on all the main Hawaiian Islands except Ni'ihau and Kaho'olawe. It grows in moist to wet forests at elevations ranging from close to sea level to 6,000 feet. It can be considered a shrub or a small tree ranging in height from 6 to 20 feet tall.

Dried or fresh mamaki leaves are used to make a tea often drunk by those feeling lethargic. The tea is also used to help with many internal disorders such as for the stomach, colon, bladder, liver, and bowels.  The fruit is eaten as a laxative or for stomach, colon and digestive problems. Infused leaves can be used in treatment for high blood pressure, high cholesterol, liver problems, and bladder problems.  In some people mamaki can cause mild agitation or insomnia.





Mamaki is the primary food source for caterpillars of the native Kamehameha butterfly. Planting this shrub in the garden will provide food for the butterfly as well as a healthy, invigorating tea for the gardener.

Mamaki is a highly variable plant. The leaves are dark-green on the top and white to gray underneath. Some varieties have reddish veins.  It is generally not suited for hot, dry coastal settings, but will grow well in urban landscapes with some shading. It will also do well planted in containers in part shade. The red-veined varieties appear to tolerate full sun better than green-leaved varieties. The mature plant recovers after pruning if no more than one-third is removed.

Mamake plants are usually propagated from seed. The fruit can be ripened in a plastic bag to soften the pulp.  Seeds are then removed from the pulp by rubbing the fruits in a strainer under running water. The viable seeds will sink and the fruit pulp and other debris can be poured off. Seeds then need to be dried on a paper towel and stored. Once planted, seedlings will thrive in a well-draining soil in a semi-shaded to shaded location.  The plants can also be propagated from cuttings.   


Ko’oko’olau Bidens menziesii is in the sunflower or aster family.  It can be an annual or perennial shrub, ranging from 3 to 12 feet in height, growing in a wide range of habitats. The plant is found on Molokai and West Maui and on the leeward slopes of Mauna Loa and Mauna Kea on the Big Island.  It is easy to grow, preferring full sun and light to moderate watering. It grows well as a potted patio plant.

Ko’oko’olau was widely used by Hawaiians prior to European arrival. Its leaves were used as a revitalizing tea. Flowers were used to stimulate appetite. Today the tea is still sold; however, Bidens pilosa is often the species incorrectly labeled and sold as the traditional Hawaiian tea. 

Saturday, February 2, 2019

Bugs - the Good, the Bad and the Ugly



Not all bugs in the garden are bad. 
Some bugs are beneficial. such as parasites and predators. The are looking for pests to consume. Two well-known good guys are preying mantis and lady bird beetles; spiders are also good predators.  Biological control can work very well. As an example, in California when certain species of whitefly came into a new area, both citrus  and some vegetable crops were damaged or completely destroyed. Yet within a number of years, their natural enemies were established, and for the most part, the pest became inconsequential.  Pollinating insect can also be categorized as beneficial.

Some bugs may be found on a plant, but are not feeding and therefore cause no damage. The bug may simply be resting or perhaps searching for nectar or another source of food.                                                                                                   
               
Some insects of course are known pests, but cause little damage. A bite may be taken from a leaf here and there,  or a little juice sucked from a stem, but overall, the plant is not harmed. 
On the other hand, some bugs do inflict damage, but it is only cosmetic. That is, the leaves or fruit may be scared or misshapen, but there is no real loss of yield.  In many cases, cosmetic damage should be tolerated. This type of damage on citrus fruit is caused by thrips and does not affect the internal quality.    
Above Photos: University of California IPM Program

And finally, if there is an infestation of an insect pest which will cause yields to be significantly lowered, the gardener will have to decide whether to wait a bit and see if biological control will work. If a parasite or predator can control the pest population, no intervention is needed. Yet if spraying is the choice, consider first a bio-rational pesticide, such as soap, oil, Bt or sulfur. These are less injurious to the environment, and may not harm the predator or parasite populations. 

And, the Ugly
Colorized image of a flower beetle
Arizona State University




Wednesday, December 26, 2018

Poinsettias

This is the time of year many people have poinsettias. What to do with them after the holidays?

Care 
  • Poinsettia plants prefer indirect light, six hours daily is ideal.
    • Poinsettias require daytime temperatures of 60 to 70°F and night time temperatures around 55°F for best growth; high temperatures will shorten the life of the plant.

    • Standing water can be harmful for the plant. Remove any wrappings from around the pot or punch holes in the foil so water can drain into a saucer; discard excess water.  
    • In some climate zones poinsettias can be planted outdoors.
    Yet, some are concerned because they think the plants are poisonous. Are poinsettias poisonous? No, this myth has been around since the early 1900’s. The American Society of Florists has been trying to dispel the myth for a long time. They say that no other commercial plant has been tested for toxicity more than the poinsettia.

    According to the American Medical Association’s Handbook of Poisonous and Injurious Plants, ingestion of the poinsettia plant has been found to produce no ill effects except an occasional case of vomiting. According to the POISINDEX information source, a child who weighs 50 lbs. would have to consume over 500 leaves before he reaches a potentially toxic level. Since the taste of poinsettia leaves is reportedly unpleasant, it is unlikely that a child or animal who attempts to eat or chew the leaves, will continue to do so after the first taste. Some people, however, can develop a skin and eye irritation from contact with the milky sap of the plant.