High Elevation Gardening Web Log "Blog"

The first thing is light which is essential for growing and flowering plants. Too much or too little light causes spindly plants, yellowing or dropping leaves, and even death. The watchwords for light are intensity, duration, and quality. Intensity is affected by exposure. A southern exposure is the most intense, eastern and western about 60% of southern, and northern only about 20%. Intensity is also affected by such things as curtains, trees, weather, season, and shade from other buildings.

The length of daylight affects photosensitive houseplants, such as poinsettia, kalanchoe, and Christmas cactus buds, which flower only when the day light is short, 11 hours or less. If more light is needed, extra light can be provided with fluorescent lights.

In placing a plant, check the tag attached to most plants, research the plant’s needs in a book or on-line, or place it where you want and see what happens. The plant will let you know whether or not it’s happy.

After light, it’s water. Incorrect watering results in ugly and unwanted plants and sadly most plant deaths. Watering depends on many factors, such as soil composition, type of pot, and room temperature as well as types of plants. Dry and crusty top soil doesn’t mean the plant needs water. The roots use the water and are generally an inch down in the pot. Put your finger down into the soil about 2 inches (about 2nd finger joint) to see if the soil is moist. If you can’t get your finger in the soil, the soil may be too dense or the plant root bound. Don’t water unless it’s dry at that depth. Water until it runs out the bottom, but don’t let it sit in water because the roots may rot. After a while, the watering needs of each plant will become evident.

Feeding is last. Plants in pots need more than water. Water leeches out many nutrients in the soil. Most plants need nutrients only during their growing seasons: March to September. They don’t need food when they’re dormant. Food comes in many forms: granular, crystalline, liquid, or tablet. The form doesn’t matter as long as the directions are followed. Most can be diluted more than suggested. Frequency depends on the vigor and age of the plant. Some need food every 2 weeks to continue flowering while others can go a month. As in watering, feeding requires paying attention to the plant.

A couple of problems unique to Flagstaff are accumulating soluble salts and lack of humidity. Some plants need extra moisture. Soluble salts can reduce growth, brown leaf tips, cause lower leaf drop off, induce rot root, stunt new growth, and bring on wilt. Other obvious signs are whitish yellow crusts and white rings on the outside of clay pots. To prevent this let the water run out of the pot when watering. DO NOT LET IT SIT IN WATER. If salts still appear, leech the pot every 3-4 months by running extra water run through the soil but not when fertilizing. If everything else fails, empty the pot, clean it well, and put in new soil.

Plants needing extra humidity, such as ferns and tropical plants, can be put or hung in bathrooms. Room humidifiers work as do trays of wet pebbles, just as long as the accumulated salts are cleaned at regular intervals.

Healthy and beautiful plants require attention and care. Neglect as with family, friends, and pets usually results in poor health and behavior. Remember: house plants are “All in the Family.”

Loni Shapiro is a Master Gardener volunteer. Dana Prom Smith, a Master Gardener volunteer, is coordinating editor for the Master Gardener Column. He can be contacted at stpauls@npgcable.com. For more information about the Master Gardener Program, call Hattie Braun, Coordinator of the Master Gardener Program, at 774-1868 ext.17 or visit our Web Site: highelevationgardening.arizona.edu.