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

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.

Reusing Potting Soil

When replanting in containers, should the old potting soil be recycled?

Reusing potting soil can work for a while; it can be rejuvenated each time by adding some nutrients and perhaps some organic matter. If a pathogen, however, whether fungal, bacterial or nematode, is introduced by way of an infected plant, the whole pot is contaminated and subsequent plantings are at risk of being infected. Have you ever planted seeds in a container and nothing comes up?  This is one reason why. 

Sanitation is important both for commercial operations as well as for the backyard. Buying new potting mix each time is the best solution. Since this can become costly, the question arises, “Can I clean up or sterilize used soil?” Here are three methods:

1) Solar sterilization, putting clear plastic over a pile of soil and allowing it to bake for 4-6 weeks, is a good idea in some locals since warm weather is required. 2) Steam sterilization is quite effective, but one must have access to steam. 3) Lastly, and perhaps the most practical for small quantities of mix is the oven. Here are the directions: place slightly moistened soil mix in a covered pan and bake in the oven at 250 degrees F for about 45 minutes.  The center of the mix needs to reach a temperature of 180 degrees F for at least 30 minutes; use a candy or meat thermometer to check the temperature.  This process may produce an unpleasant odor.  

Used potting soil can be thrown in a garden compost pile. Alternatively, a designated pile of used potting soil only can be created. When the process is complete, the soil is able to be reused for container purposes. This procedure will be relatively safe if either compost pile heats to proper temperatures, and the heating is uniform. Ideal temperatures range from 104 F. for 5 days to 130 F. for 4 hours. 

If potting soil is reused, I would recommend a type of crop rotation. Whether vegetables or annual flowers, replanting with the same species of plant or even in the same family is not advisable. For the next planting, rejuvenate the soil and plant with a different family of plants. In conclusion, gardeners have been successful in reusing soil mixes; nevertheless, the above information is useful for making an informed decision.

Watering House Plants

Many people have asked about the care of indoor plants, “How often should I water?” The answer I give will apply to plants in the house, in an office setting  or on the lanai or porch.

1)  Do not water plants by the calendar, even though it seems the easiest way. Using this method assumes that environmental conditions such as temperature, humidity, wind, etc., each day of the year will be the same.

2) Water by inspection of the soil. If the soil is wet, wringing wet, don’t water; if it’s dry, water the plant.  If it’s 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 test the surface, which usually dries out rather quickly.  To truly evaluate the condition the soil of a potted plant, 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 you will have arrived at it through observation and inspection. 

3) 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 has 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 slow 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.

Whether under watering or over watering, the leaves wilt. It is important to note that under watering a plant will lead to  non-vigorous growth and low fruit production for fruit producing plants, but over watering can easily lead to the death of the plant.

Knowing when to water will take some experience, and some trial and error.  It is important to use a well-drained potting mix and never leave water standing in the tray. (Discard the water; don't reuse it.) Plants that have been in the pot a long time may 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.

Perils of Watering Houseplants

For those who choose to beautify their home with house plants, here are tips to help avoid some of the common causes of plant death.

Some people under water their houseplants.  This is not disastrous; the plants won’t grow as vigorously as well watered plants. And if the plant is wilting, adding water, in most cases, will revive it.

On the other hand, overwatering can often be the death of a plant.  Many people gauge watering by looking at the surface of the soil.  The problem is that the surface may be dry, but down a few inches and more, where the roots are, the soil is still wet.  This is especially true with nonporous containers.  Digging with a small trowel or even a finger will indicate if the soil is moist below the surface. 

Worse yet, some people will irrigate on a schedule. The water requirement of plants, however, will vary depending upon temperature (winter/summer), humidity (rain/shine), drafts (open windows), and the use of heaters, fans or air conditioners. The soil is the best indicator not the calendar!

After watering, the excess water needs to be disposed of.  Leaving standing water can lead to serious root rot.  

Benefits of Houseplants

A few, well-placed houseplants can transform a dull room into an attractive, warm environment. Plants add character, charm and beauty to a dwelling. But they do much more.  Indoor plants can clean the air and enhance creativity. Currently many hospitals encourage visitors to bring in plants. More than a cheerful greeting, plants provide oxygen to patients and cleanse the air.

The good news about these living air cleaners comes from a classic study by NASA. They found that plants can take airborne chemicals that are toxic and convert them into an energy source for the plant. The studies reported that houseplants were able to remove up to 87 % of air toxins in 24 hours. They can eliminate a variety of toxic air emissions including formaldehyde (found in particleboard, fire retardants, natural gas and cigarette smoke), benzene (found in inks and paints), trichloroethytene (found in paints and varnishes), and carbon monoxide, xylene and ammonia. The above chemicals and other nasty pollutants can also be found in carpeting and cleansers. Using a variety of indoor plants will purge many toxins from the home.

How many plants are needed to keep a home clean?  Recommendations vary from one or two good-sized plants per room to 15 to 18 plants for a 1,800 square foot house.  The point is the more house plants, the better it is.  However, having this many plants in a home could potentially produce lots of mold from the moist soil and decaying organic matter. It’s crucial not to over-water plants. Placing a layer of small gravel over the topsoil may help to minimize the mold.

Other studies have shown that indoor plants can reduce fatigue, coughs, sore throats and other cold-related illnesses by more than 30 percent, partially by increasing humidity levels and decreasing dust. Note: this study was done at the University of Agriculture in Norway which has a very dry climate.

Indoor plants are good for businesses, too. When a manufacturing company integrated living plants into its office, company administrators noticed enhanced creativity and increased productivity in their employees.

Keep in mind, some houseplants are poisonous and should be handled with care, or not at all, especially if there are small children in the home. Some of the common, poisonous, indoor plants include dieffenbachia (dumb cane) and philodendrons. These plants contain oxalate crystals. Chewing a leaf or stem may cause mild to severe swelling and burning of the mouth, tongue and throat along with choking. If the skin is exposed to the plant’s sap, where the abrasive oxalate crystals are found, an uncomfortable skin rash can develop with burning, redness and itching.  

Controlling Pests on Houseplants

                                                  
 Houseplants are susceptible to many unsightly insect and mite pests. Some pests cause extensive damage, while others are merely a nuisance.

Here are some control measures:

·        A healthy plant is much more resistant to insect and mite injuries.  Keep house plants well fertilized and adequately watered. Keeping the soil excessively moist favors the development of root rot along with an increase of nuisance pests like the fungus gnat.  When soils are kept too dry, plants are prone to mite problems.

·        Many infestations are brought home with a newly acquired plant. Carefully inspect all plants that are taken home. 

·        Syringing plants - many household plant pests can be controlled, at least in part, by washing the plant periodically with a vigorous jet of water. This is particularly effective for spider mites and aphids, which are readily dislodged.

·        Vacuum – if you have whitefly problems, the regular use of a small, hand-held vacuum can assist in controlling this pest.  Careful not to vacuum up the plant!

·        Sanitation - Seriously infested plants are often best discarded. They can serve as a source for infesting other plants.

·        Alcohol – use  Q-Tips dipped in alcohol to wipe small infestations from the plant.

·        Pyrethrins, synthetic pyrethrins (known as pyrethroids), insecticidal soaps, horticultural oils, Neem (derived from seed extracts of the neem plant) and Neem oil can all help in controlling most houseplant pests. Some insecticides, especially the oils, can burn some of the more delicate houseplants.  When in doubt, spray one or two leaves and wait 3-4 days before spraying the whole plant. 

·        There are also systemic insecticides which are absorbed into the plant. As the insect or mite feeds on the plant, they will die.  Look for an insecticide with the active ingredient, Imidacloprid.

                                                                        Mealybug on Palm

Safety Issues:                                    

Only use pesticides that are specifically labeled for use on houseplants. Most yard and garden pesticides do not allow this use.  If possible, take the plant outdoors before spraying to minimize pesticide exposure within the home. When using aerosol sprays, do not apply closer than 18 inches to the plant or injury may occur from the spray.