Plants grown in homes or offices usually have a diminished need for watering since light levels, low humidity and cool, comfortable temperatures are constant. Over-watering is the most common reason plants meet their demise in an indoor setting. Monitoring soil moisture and watering only when soil is dry prevents multiple people from watering on an unnecessary set schedule.
There may be the simple misconception that plants need water as frequently as we or our pets need a constant supple and access to water. However, over-watering can be among the fastest ways to kill an indoor plant. The constant, comfortable temperatures with low light lowers the need for water when compared to the more challenging outdoor garden with fluctuating variables.
In the office, there may be several people that water or assume they are maintaining the same plant, so inconsistencies in a person's perception of "how much water" and "when to water" can find a poor office plant being "over-loved." Moreover, without a consistent standard to measure soil moisture, whether by touching the soil by hand or the use of a soil moisture meter, arguments can occur over how the plant should be maintained.
Many symptoms that can arise when an office plant is being over-watered. Just like when you under-water, leaves will also turn brown on their tips or edges when you over-water. Mold may be seen growing atop the soil in the pot, or the saucer under the pot may have a foul-smelling or constant reservoir of water.
Office plants that flower will usually prematurely drop their flowers, flower buds or leaves when over-watered, much like when a plant is starved of moisture, too.
Pressing your index finger into the top inch of soil in the container should never feel like a wet sponge, as soil particles should barely stick to your skin when the plant's soil moisture is slightly moist.
When to Water
Avoid watering plants on a strict schedule, a practice so common for other activities in an office environment. Plants need watering only when they truly need it, which may vary by time of year, proximity to a window or whether the air-conditioning or heating system is running.
Use a soil moisture meter tool, whether with a scientific gauge or a color-changing clay to help inform you of when to water. Touch the soil surface with your bare fingers. If soil feels wet or soil particles do not stick to the moisture on your skin, do not water. Wait until the soil feels barely moist to the touch and soil particles stick to your skin. And then, look at the plant to see if there are signs of water stress such as wilting or yellowing leaves. Sometimes it may be best to wait one more day after you think you should water based on these tests: this ensures you are never over-watering.
There are two common techniques to water the office plant: basin filling or on the soil surface. Most people are accustomed to pouring water atop the soil and watching it soak away. Enough water should be applied so that a little water finally trickles out of the pot's bottom drainage holes. To avoid a mess, relocating a potted plant to the office kitchen or bathroom sink while watering ensures the drainage of water is complete before replacing it back on the desk.
Another technique, which is better suited to plants known to appreciate wetter soils, is basin filling. The saucer or basin placed under the office plant is a reservoir to collect water. Filling the basin also will allow water molecules to move upward into the soil via capillary action. Note how long the water takes to be fully absorbed into the pot, sometimes repeated basin fillings are needed to water the plant. Touch the soil surface, too, to note if it feels bone dry or damp. Never allow basin water to remain full, in general, for more than two days. Empty the basin so you do not suffocate plant roots in excessive water.
Appropriate Indoor Plants
Not all plants are created equally, especially with regard to adaptability to office environments or tolerances to neglect. Seasonal potted plants like Easter lilies, azaleas or poinsettias are best used only for a short duration, when they are at their best. Dispose of higher-maintenance plants to diminish the worry about watering and care.
Plant species that are naturally suited to low light, drier ambient humidity and the occasional short-lived soil drought are ideal. Some good choices for office plants that tolerate occasional cyclic bouts of over-watering followed by a forgotten watering include snake plant (Sansevieria), Chinese evergreen (Aglaonema), peace lily (Spathiphyllum), lady palm (Rhaphis excelsa), corn plant (Dracaena fragrans)and ZZ plant (Zamioculcus zamiifolia).
Certainly other plants can be grown and become beautiful indoors in an office, but the caretaker must be aware of the individual plant's watering needs and growing preferences. Popular plants to try in brighter light nooks of the office include bromeliads (Guzmania, Neoregelia, Tillandsia, Vriesea), cactus and succulents like yucca.