Monday, August 31, 2015

Tomatoes with Blossom End Rot

What causes the bottom end of green tomatoes to rot?
Blossom end rot (BER) is a physiological disease. This type of disorder is caused by something other than a fungus, bacteria, virus, etc., and therefore there is no need to spray with a pesticide.

Symptoms may occur at any stage of fruit development but most often on the immature, green fruit at one-third to one-half full size. Tomatoes will show light brown spots at or near the blossom end, and while ripening, these spots gradually expand into a sunken, leathery, brown or black lesion.  Sometimes hard, brown areas develop inside the fruit.

Recent studies show that blossom end rot results from a low level of calcium in the fruit. Adding lime to the soil will help prevent this problem.  

BER is aggravated by excessive amounts of fertilizer, particularly nitrogen and low soil moisture or irregular watering patterns. Use nitrate nitrogen as the nitrogen source. Ammoniacal nitrogen may increase blossom-end rot as excess ammonium ions reduce calcium uptake. Fertilizing with nitrogen during early fruiting should be avoided. Drought will increase BER along with wide fluctuations in soil moisture; mulching will help.

BER is more common on sandier soils. Some varieties are more affected than others. Check seed catalog descriptions for those varieties that are resistant. Peppers, eggplant and zucchini squash  can also be susceptible to BER.

Monday, August 24, 2015

Rainbow Shower Trees

In late summer and early fall, the beautiful, multicolored rainbow shower trees display a stunning display of pink, white, orange and red flowers. These rainbow trees (Cassia x nealiae) are actually a hybrid between the golden shower (Cassia fistula) and the pink shower (Cassia javanica). There are different varieties, each with a different array of stunning color combinations: orange, pink, white, peach and sherbets.

The tree itself is fast growing reaching up to 65 feet high and spreading branches like an umbrella. It is fairly drought tolerant but grows best in a hot tropical or subtropical climate. Trees can be propagated by air layering or grafting and are native to Southern Asia.

In  Hilo, Hawaii, these beautiful trees can be found lining Kamehameha Avenue along Hilo Bay and growing at Liliuokalani Park. In addition, a few other types exist in Hilo:
  • The white shower tree, producing creamy white blossoms with a hint of yellow, are also be found in Downtown Hilo.
  • The pink shower tree producing large showy pink flower clusters can be found on the Hawaii Community College Campus.
  • The golden shower tree produces brilliant yellow flowers and can be seen at the Kawamoto Swim Stadium and near Mo’oheau County Park.

Monday, August 17, 2015

Pepper Blooms and Small Fruit Dropping

Flower and fruit drop of bell peppers is caused by the pepper weevil. Both the mature black weevils and the small white worms (the weevil larvae), can often be seen when the fallen fruit is cut open.  Holes are made in the young pepper and in flower buds either by the feeding of adult weevils, females laying eggs or by emerging adults.  Infested peppers that do not fall and rot but go on to maturity, will have blackened seeds and cores as a result of larval feeding. Mature peppers are not susceptible to weevil attack, because the skin is usually too hard.

Sanitation is very important in controlling this pest. Remove all peppers that have dropped to the ground. For the next planting, rotate to another non-solanaceous  crop, do not plant tomatoes or eggplant; control solanaceaous weeds. If weevils increase and cause major damage to the crop, there are registered pesticides available such as carbaryl (sevin). Pyrethrin may be acceptable for use on organically certified produce.

Photos: University of Arkansas 
             University of Florida

Monday, August 10, 2015

Edible Monstersa

Monstera deliciosa is a native of Mexico and Central America. It is a climber that under excellent growing conditions can reach 70 feet with leaves measuring 3 feet across. It has aerial roots which cling to a support or will form a dense mat on the ground when unsupported.  The plant grows well in a well-drained soil, rich in organic matter.

Warning: all parts of this plant are poisonous. Symptoms include intense burning of mouth, tongue, and throat; nausea, vomiting, and diarrhea may also occur. Furthermore, contact with cell sap may cause skin irritation. The edible parts of the plant are only the ripe fruit. Some people, however, are even allergic to it.  For those who are not allergic, eating large quantities of the fruit at any one time is not recommended. The toxin is the needle-like calcium oxalate crystals and possibly other unidentified toxins. This chemical is also found in the taro plant, rhubarb and other plants in the Araceae family.

Mature fruit that is ready to harvest will turn from green to a lighter green and the tile-like segments, or caps at the base of the fruit will begin to separate slightly, making it appear somewhat bulged. This usually takes place about 12 months after flowering.  Fruit may then be cut from the plant, leaving 1 inch or more of the stem. To ripen the fruit, keep it at room temperature for up to 6 days. Sometimes fruit is placed in a paper bag during the ripening process.

During this time the fruit will ripen as the green caps will easily fall from the fruit and expose the edible portion beneath. Fruit ripens first at the base, moving toward the apex (top). Do not eat from any section where the caps have not been shed. The pulp should only be eaten from that portion of the fruit that easily falls off the core (stem). This is because immature sections of the fruit contain the oxalate crystals that cause severe discomfort when swallowed. Leave the unripe section in the paper bag until the next portion is ready to eat. Alternatively, information from Australia indicates that the whole fruit can be ripened for eating at one time by standing the base in water and keeping it in the dark for a few days. The ripened pulp may be stored for several days in the refrigerator before consumption.

In general, monstera is eaten as a fresh fruit, although the pulp may be used as an ingredient in desserts. It is said that the ripe fruit taste like a combination of banana, pineapple, and cherimoya (custard apple). Others add flavors such as grape, strawberry and mango. In fact, because of these strange all-encompassing flavors, monster is sometimes called the fruit salad plant.
In addition to the above written description of the mature fruit, I would urge interested readers to search ‘eating monstera’ on YouTube. There are some good videos, as the saying goes, “A picture is worth a thousand words.”  

Photos: University of Wisconsin Master Gardener Program