Monday, March 30, 2020

Why fruit trees don’t produce.


Since there are many factors involved in fruit production, there are also many reasons why fruit trees don’t produce.  Here are a few of the more common ones.
·        Rain- Too much rain during the bloom period can wash pollen away,  and a forceful rain along with wind can actually knock blossoms off.  Also, bees tend to fly less, or not at all, during heavy rains.
·        High heat and low humidity during bloom will hamper pollination.
·        Juvenility  - Sometimes it takes many years before a tree will produce fruit; mangosteen is a good example. However, new evidence indicates the size of the tree is more of a factor than age. In general, trees grown from seed take longer to produce fruit than those that are grafted, budded, or air layered. 
·        Pollinators – Some fruit trees require more than one tree or one variety in order to set more abundant fruit.  Examples are rambutan, macadamia, and avocados.
·        Some trees require insects to help in pollination, such as durian. 
·        Lychee and longan need a combination of low temperatures, 50 -59 degrees Fahrenheit, and a dry period (4-6 weeks) before bloom occurs.  Bloom for rambutan will be enhanced in response to drought.
·        The deciduous fruit trees, like peach, plum, nectarine, apple, etc., require cooler temperatures for good fruit production. This chilling requirement is the number of hours the tree needs to experience below 45 degrees F.  This requirement differs among species and varieties, ranging from a few hundred hours to over a thousand. 

Monday, February 3, 2020

Cilantro or Coriander?





Most chefs are familiar with the seasoning coriander. Coriander is actually the small, dried fruit, often referred to as the seeds of the cilantro plant. In fact, the scientific name for cilantro is coriandrum sativum, or coriander, also known as Chinese parsley. The fresh leaves and the small dried fruit are the parts most traditionally used in cooking.

The fresh leaves are often used in South Asian and Chinese cooking as well as in Mexican cooking, particularly in salsa and guacamole.  Since heat will diminish the flavor, leaves are frequently used raw or added just before serving. The leaves lose their aroma when dried or frozen.

Coriander seed is a main ingredient in garam masala, an Indian spice, and in curries. Although the ingredients in garam masala can vary, it commonly includes coriander, black pepper, cumin, cardamom and cinnamon.  In India, roasted coriander seeds, called dhana dal, are eaten as a snack.

Coriander is used for pickling vegetables and for making sausages in Germany and South Africa. In Russia and Central Europe, the seeds are used as an alternative to caraway seeds. Even in brewing certain types of beer, particularly some Belgian wheat beers, coriander is an added flavor.

The Problem of Bolting


Cilantro is a cool season plant. It flourishes during cool nights and moderate, sunny days as in the spring and fall. But it will bolt at the first sign of hot weather. Bolting is the premature flower formation initiated by hormones within the plant system in response to high temperatures, as well as drought and starvation.  This unwelcome occurrence in leafy vegetables such as cabbage, lettuce and cilantro, takes the plant out of its leaf producing mode and switches over to flower and seed production.  

On the Big Island of Hawaii, the Volcano and other similar areas would perhaps give cilantro the longest season, provided there is adequate sunshine. Cilantro, however, is a true annual and even under the best conditions, it will send up flowers and eventually die within the year. In order to minimize the bolting effect, cilantro should not be grown during the warmer, summer months. The best time for planting would be after the summer heat from September or October until perhaps March.

There are some slow-bolting varieties, Calypso is one, that can extend cilantro’s productivity perhaps a month. Snipping off the first newly emerging flower buds may also extend the leafy period, but only slightly. 
 
Like many plants, coriander may contain properties useful in the treatment of Type 2 diabetes and high cholesterol.  Research is presently investigating these claims and other medicinal attributes of coriander.  

Thursday, December 26, 2019

All Toads Are Frogs, But Not All Frogs Are Toads


How to control toads and frogs in the garden?

Having found no control manual for toads and frogs, the common sense approach is to change the habitat to make it unfriendly for them. This will include eliminating water sources for their reproduction and moist areas for them to hide – almost an impossibility in areas of heavy rain! But eliminating piles of yard rubbish and trimming back thick ground cover will help. Various types of barrier-fences can be erected either around the property or just around certain desired areas. Since toads and frogs eat insects, controlling the bugs would also be a way of discouraging their presence, again not practical for backyards in Hawaii. But eliminating any outdoor lighting, which attracts many insects, should help. 


For clarity, all toads are members of the family Bufonidae, which falls under the order of Anura, commonly called frogs. Therefore, all toads are frogs but not all frogs are toads.

Toads tend to have a thicker skin allowing them to live away from water longer than most frogs. A toad’s skin is often covered with bumps and glands. The similarities are that frogs and toads both reproduce and develop in water, both ‘sing’ and are both carnivorous.

Of note, when the bufo toad is attacked, its defense is to exude a milky fluid known as ‘bufotoxin’. This poison protects it from some predators but not all. Most snakes and birds seem to be unaffected. Humans need to be careful since the toxin may cause skin irritation and possibly worse, but there are no reports of human fatalities. Unfortunately the toxin can be fatal to small animals such as cats and dogs.  Thus ridding the yard of bufo toads is a protection for your pet.

Pictures from Forest and Kim Starr: Bufo marinus, The Cane Toad