Monday, November 17, 2014

Hummingbirds and Pollination





 

About 25% of plants are wind pollinated. The rest rely on pollinators: bees, bats, beetles, butterflies and yes, hummingbirds, as well as some other birds. During the day hummingbirds feed about every 10 minutes and consume up to 2/3 of their body weight from the nectar of plants; they can service 20 flowers per minute. The wings of hummingbirds beat up to 55 beats per second and allow these tiny birds to fly at speeds up to 50 mph. They can hover and even fly backwards or upside down. 

Hummingbirds are primarily attracted to tubular flowers. They are stimulated by color, especially the color red. Clumps of bright red, orange and pink flowers are more visible to them than other colors. Plants with red, tubular shaped flowers are an excellent choice in the garden to attract hummingbirds. Other plants that attract these birds are gladiolus, honeysuckle, iris, lupine, nasturtium, petunia, and cosmos. 

Lastly, I was asked if hummingbirds pollinate vegetables. I am having difficulty finding specific vegetables that they pollinate. That’s probably because there are not many vegetables with red, tubular shaped flowers, which attract the hummingbirds.  

Photo: University of Maine

Monday, November 10, 2014

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.

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.

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.   

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.

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. 

Monday, November 3, 2014

Watering Houseplants




How often should I water my houseplants?
  • Although is may seem the easiest method, do not water plants by the calendar. Using this method would assume that in regards to environmental conditions (temperature, humidity, wind etc.), each day of the year will be the same.
  • Water by inspection of the soil or potting mix. If it is wet, wringing wet, don’t water; if it’s dry, water. If the soil is moist, but not soaked, wait a few days and check again. If you actually observe the plant wilting, you should have watered yesterday. When assessing the soil, do not examine the surface, which usually dries out rather quickly. To truly evaluate the condition of the soil, place your finger about a third of the way down the pot or take a mini trowel and pull up some dirt. In reality, you may end up watering somewhat by the calendar, but at least you will have arrived at it through observation and inspection. 
  • The lifting method also works well. If the pot isn’t too big, simply lift the pot off the ground, if it’s heavy, it’s got plenty of water. In comparison, if it’s relatively light, it’s time to water. Putting these methods together, you’ll soon get the hang of it.

A major problem lies in the fact that wilting and lack luster growth can be symptoms of both under watering and over-watering. In the case of over-watering, the roots will begin to rot, with or without the help of soil pathogenic fungi. Once some of the roots are gone, the plant will not be able to pick up enough water, especially on hot days, and the leaves wilt.

It is important to note that under watering a plant will lead to lackluster growth and low fruit production (for fruit producing plants), but over-watering can easily lead to the death of the plant.

As you can see knowing when to water will take some trial and error. It is important to use a well-drained potting mix and never leave water standing in the tray. Plants that have been in the pot a long time may have become pot bound, meaning that most of the space in the pot is occupied by roots rather than soil. If this is the case, you will find that these plants need very frequent watering because there is simply no soil to help hold the water.