Tom Karwin, On Gardening | Caring for problem indoor plants

Care for your garden

Our recent welcome rains provide opportunities to enjoy indoor plants This column does not provide basic care for such plants. Good information is available online (see “Advance Your Gardening Knowledge,” below). Instead, we are focused on indoor plants that have become overgrown or otherwise need management.

We provide four case studies of problem plant care, describing approaches that could be adapted for the potentially large range of challenges.

The Amazon Lily (Eucharis amazonica, from Peru) has attractive leaves and the promise of producing waxy white fragrant flowers on 18-inch stems during two periods: July-August and December-March. Still, this plant been growing indoors since 2015 without yielding a single blossom. A search of the internet located advice to provide indirect light (which it has received) and consistent moisture during growing periods (out of sight, out of mind). Other advice is to avoid repotting, because the plants prefers to be root-bound. The plan: relocate the plant (with minimal root disturbance) to a location where it will receive more indirect light and regular irrigation and install it in a smaller container to let it fill the available root space.

The Amazon Lily is an asset for its foliage, plus the promise of scented blossoms. (Tom Karwin — Contributed)

The Coffee Plant (Coffea arabica ‘Nana’, from Ethiopia) is an evergreen foliage plant for indoor cultivation. There are some 16 varieties of this plant, some of which can grow to a height of 5 feet, but the ‘Nana’ cultivar will reach only 12-inches tall. internet research revealed that this plant will develop pure white, slightly scented flowers and beans only after four-to-eight years of growth. This specimen has been growing under good conditions in the same container for several years without blossoming, so it might just need more time.

Still, the plant had become crowded in the container and the soil level was quite low, leaving insufficient space for root growth. The plan: lift the plant and add enough potting soil to one inch below the rip of a typical container, so that the plant could be watered without an overflow. This soil level also allows the optional addition of a decorative top dressing. This process revealed a dozen divisions, most of which were 6-8 inches tall. We replaced the larger divisions in the original container and moved the smaller ones to grow in a different container.

Then, we have a widely grown Parlor Palm (Chamaedorea elegans, from Mexico). The plant has graceful pinnate fronds, i.e., a series of leaflets on either side of a midrib. The specimen of current interest has been growing in the same container for several years. It has a healthy appearance, 7 feet in height, and small cluster of black berries on orange stems. It seems spindly, however, and requires support to remain upright. This growth could be the result of insufficient light. The plan: internet references indicate that this plant should not be pruned to control height, as can be done with some plants; it would be fatal for Parlor Palm. The stem could be severed below adventitious roots, if they are available along the stem, and re-rooted. This plant is not showing such roots, so the best option is to provide greater indirect light and hope for more sturdy growth.

Our last example is a Dwarf Umbrella Tree (Schefflera arboricola, from Taiwan and Hawaii). It could be a ‘Gold Capella’ cultivar. This popular houseplant has glossy green palmate leaves (i.e., leaflets radiate from central point) with an attractive creamy variegation, and rarely flowers indoors. When grown indoors, it usually grows to 3 feet tall, but could reach 6 feet. The plant in question has rangy branches more than 6 feet in length. This condition, called etiolation, results from insufficient light. An online search described a simple solution: cutting the over-extended stem to the desired height. The plant will rebound quickly and soon produce a more compact, lush form. The plan: hard prune the leggy stems to 6 inches high and relocate the plant to a higher level of indirect light. (Direct light would burn the leaves.)

A common issue among these problem plants is the right level of indirect light, which is measured in foot-candles. One foot-candle (fc) is defined as one lumen per square foot.

A low level of indirect light would be 20–100 fc; a moderate level would be 100–1,000 fc; and a high (or bright) level would be 1,000+ fc.

When adding an indoor plant to your home, look for notes on the plant label or on the internet for the plant’s preferred level of light. This information well be expressed informally, and rarely in foot-candles, so good practice includes monitoring the plant’s growth. If the plant is stretching, move it to a spot with more light. If it shows signs of leaf scorch, give it less light.

It is also appropriate to consider the normal variation of natural light levels.

There is an inexpensive way to measure foot-candles, if you have an Apple iPad and a desire for precise care of your houseplants. The application, “Light Meter,” is available for $1.99 on the Apple App Store.

Advance your gardening knowledge

For more basic advice on managing your houseplants, has two free video tutorials: search for “Houseplant Care 101” or “Houseplant 101.” Each of these presentations are within a larger collection of brief video recordings about house plants. To see the full listings, search for “Planterina,” which also has a website,, or “Plant One on Me” with Summer Rayne Oakes, who also has a website,

As always, when you know the botanical name of your plant, you can use it to search the Internet for specific cultivation advice.

Enrich your gardening days

Indoor gardening offers many opportunities for filling the suitable space that’s available in your home. There are small and large plants, genera and species that grow nicely with indirect light (given all the desired conditions of soil, moisture, fertilization, etc.), several very popular options, and the potential for collecting exotic varieties.

Keep your emotions positive and your viruses negative and enjoy your garden.

Tom Karwin is past president of Friends of the UC Santa Cruz Arboretum, Monterey Bay Area Cactus & Succulent Society, and Monterey Bay Iris Society, and a Lifetime UC Master Gardener (Certified 1999–2009). He is now a board member and garden coach for the Santa Cruz Hostel Society. To view daily photos from his garden, To search an archive of previous On Gardening columns, visit

Contributed by local news sources

Next Post

President-elect Biden blames President Trump for violence at Capitol that's shaken US

President-elect Joe Biden on Thursday denounced the rioters who stormed the U.S. Capitol as “domestic terrorists” and he blamed President Donald Trump for the violence that has shaken the nation’s capital and beyond.The riot by Trump supporters who breached the security of Congress on Wednesday was “not dissent, was not […]