Houseplants are a diverse group; the term is used to describe everything from a cactus to an orchid. This diversity can make plant care challenging (and occasionally frustrating). There are some pretty simple and common things to remember when selecting and caring for houseplants.
If you haven't purchased a plant yet, choose a healthy plant to begin with:
Without light a plant will starve, unable to produce food, or photosynthesize. (Plant photosynthesis is also the process that removes carbon dioxide from the atmosphere, replacing it with oxygen). So, the placement of your plants in the home is critical. A home will contain many microclimates; for example kitchens and baths normally are more humid. Plants do not have to reside on a windowsill, but if yours do, here are some enlightening facts.
Remember that windows facing:
More Light Facts
As stated above, most plants do their growing at night. Just as plants need light to produce food, they also need a daily period of cool and dark to prosper. Temperature needs vary by plant, but on average, houseplants enjoy temperatures ranging from 65° to 80° F during the day and 55° to 65° F at night. Today, most homeowners tend to maintain a constant temperature, averaging around 70° F. Most plants will adapt to this temperature, but some flowering plants cannot set new flowers without cool evenings.
As always, read the plant label for its specific requirements.
Overwatering is the most common cause of plant death. Roots need air as well as water. Soil that is too wet will begin to smell, the roots will rot, and diseases will find a home in the wet environment.
When to Water
Some plants need constant moisture; some prefer a much drier environment. The good old standby test is to stick your finger into the soil to a depth of 1 - 1 1/2 inches midway between the rim of the pot and the base of the plant. If the soil feels dry, then it’s time to water. In most cases, watering should be done in the morning. As you've probably heard, plants don't like to go to bed with wet feet.
How to Water
Water must reach all of the root system to be beneficial, so when you water, do it generously rather than a little every day. Always read the plant tag for specific instructions. Water around the base of the plant, not over the flowers or foliage. Use room temperature or tepid (around 90° F) water. When water begins to flow from the drainage hole - stop. Pour off the excess water from the saucer. If the water comes out of the drain hole immediately, the plant may be completely dried out.
Another sign of an overly dry plant is when the soil is pulled away from the outside edge of the container. An extremely dry plant can be immersed in a sink or other container of water for about 30 minutes. The moisture will be drawn up through the drainage hole.
Wicks and self-watering systems are options you may want to consider. Wicks are inserted through the drainage hole. The pot sits slightly elevated in a saucer or other container (not directly in the water). The other end of the wick is placed in the saucer, which contains water. The wick ensures that the soil will remain consistently moist (as long as the water level is maintained in the saucer).
Homes are generally dry. Additional moisture can be provided by grouping plants or placing in a tray on a layer of damp pebbles. Smooth-leaved plants can be misted or washed. Do not spray or wash a hairy-leaved plant (such as an African violet).
The growing medium is an important aspect of plant care. Your best bet is to buy prepackaged soils. Soil from your garden could contain fungi, bacteria, insect eggs, weed seeds or undesirable elements that you wouldn't want to bring into your house.
The most common types of bagged soil include:
Potting mix - the best choice for potting or repotting. Potting mix should contain organic matter, as well as elements for aeration and moisture retention (perlite and vermiculite). Charcoal may also be an ingredient.
Professional grower's mix - also known as greenhouse mix. Because of its fine texture, it is very good for starting seeds. But for the same reason, it will also dry out very quickly.
Planting mix - contains compost and sand and is recommended for outdoor use, not houseplants.
Topsoil - is basically compost. Because of the rough texture, it's best to use in the yard, not as a potting soil.
Flowering plant mix - contains more acid to promote flowers, otherwise similar to potting mix.
Cactus mix - absorbs water easily, and then dries quickly. Use with cacti and succulents.
A houseplant's root system is limited by the boundaries of its container and cannot go in search of food as an outdoor plant will. For that reason, feeding is necessary for a healthy plant. Nitrogen, phosphorus, and potassium are the three main nutrients contained in most plant foods.
Fertilize houseplants during their growing (not dormant) season. Too much fertilizer can damage a plant. Specific needs will depend on several factors - the plant itself, the amount of light it requires, whether it is a flowering or foliage plant. In general, plants that require more light will require more frequent feeding. Above all - read the label on the plant food.
The container of the plant affects how often you should water it. Clay dries out more quickly than plastic since the material is porous which helps prevent the soil from getting too saturated. Because of this same characteristic, plants in clay pots may need watering more frequently. Clay pots can be waterproofed if you wish.
Other waterproof containers, such as plastic and ceramic, will definitely hold water, so look for a container with a drainage hole. Drainage holes allow excess water and harmful salts to escape. Remember any pot with a drainage hole in the bottom needs a saucer underneath.
Within a plants' lifetime it may become necessary to move it to a bigger container. A few plants need to be slightly rootbound in order to prosper but most plant need additional space as they mature. Repotting is essential to allow root growth.
When the time comes to repot, you may see some of the following signals:
Follow the steps below to repot your plant:
Prepare a clean, dry pot - no more than two sizes larger than the old one. To prevent soil from running out when watering, place a piece of a broken clay pot over the drainage hole. Then add a layer of potting soil.
Support the plant with one hand by placing the plant stem between your fingers. Turn the pot upside down and tap with the heel of your other hand. If the pot sticks, tap it in other areas (a little more force may be needed if the plant is severely rootbound). Gently remove the pot.
Remove dead or damaged roots.
Carefully break up the mass of roots from the side and bottom of the root system. Remove all the loose, old soil from the top to a depth of about 1/2-inch.
Place the plant into a new pot and add more soil. Gently tamp with your fingers. When you think about it, a plant doesn't really grow in soil, but in between pieces of soil, so don't pack it too tightly. Fill the pot with soil until it's about 1/2 to 1 inch from the rim of the new container.
If temperatures are very hot, or the air is dry (during winter months), spray the leaves every day. If the soil is too high or too low in a pot, you run the risk of water running over the edge of the pot or water standing inside. Around one inch from the rim is good (a little less in a small pot).
To prune - pinch off new shoots during spring and summer to promote a bushier plant and flowering. This will also delay the need for repotting. Prune a leggy plant just above a leaf joint.
Office plants may need a little special attention. Offices are usually drier and draftier than a home. Lighting can vary from large windows to dim fluorescent bulbs. Office schedules often will mean 5 days of regulated temperatures and light followed by 2 days of reduced temperature control (warmer or cooler - depending on the season) and practically total dark. For this reason, foliage plants tend to do better than flowering plants for the office environment.
Dormant, Not Dead
Many flowering plants, such as cyclamen and gloxinia, have a resting period or dormant stage. Some may simply stop growing during this period, while others may wilt and lose foliage. In fact, some plants have been discarded as dead during dormancy. Dormant plants do not need as much water or fertilizer. While winter is the most common dormant period for plants, check for detailed information on your houseplant.
In spite of their diversity, indoor plants are pretty durable and forgiving. Houseplants can live for many years, giving us the benefits of their beauty and a healthier indoor environment. All they ask in return is a little attention. Just remember that plants and their individual needs vary. Read your plant tag and know your plant.