HOUSEPLANTS Presentation based on Chapter 17 Beth Fausey-Shecklehoff LEARNING OBJECTIVES Understand factors to consider when selecting a plant to grow indoors. Describe how to acclimate houseplants to an indoor environment. Describe how light varies with windows facing north, south, east and west. Determine two methods to water houseplants and the benefits of each. Determine whether a houseplant is pot bound and how to select a new container. SELECTING HOUSEPLANTS Houseplants are simply plants taken out of their native habitat and grown in a different indoor environment. Cultural requirements: Successful gardeners pay close attention to the growing medium, light, temperature, water, humidity and fertilization provided to houseplants. Lifetime: Gardeners should consider the desired length of indoor performance they wish to achieve when selecting an appropriate houseplant. Size: Plant size is an important consideration in selecting houseplants. SELECTING HOUSEPLANTS (cont.) Potential toxicity: When selecting a houseplant, it is important to know that a few common houseplants can be toxic and/or poisonous if eaten or touched by children, adults or pets. The New York Botanical Garden’s website provides a listing of such houseplants. Plant health: Gardeners should purchase healthy, well-potted plants that have full foliage canopies and are free from insects and disease. Once home, quarantine new plants in an area away from existing houseplants for several days to weeks. T Degree of difficulty: Some plants can be more challenging than others to grow. These plants include cacti (high light, well drained media and proper watering), ferns (high humidity levels, adequate water and appropriate light levels) and flowering potted plants (specific light or temperature requirements for rebloom). These plants are all going to the same home. PREPARING PLANTS FOR THE HOME ENVIRONMENT Selecting a Container/Consider: Drainage is critical Size demands that the pot coordinates well with the plant size Fillers a thin layer of drainage material may be beneficial Material pots may be unglazed clay (excellent aeration), glazed ceramic, plastic and fiberglass (easy to clean for reuse), options such as terrariums, bottle gardens and dish gardens. Self-watering containers are available with built-in-water reservoirs. Growing Medium A quality growing medium or potting mix will help plants thrive. These potting mixes must support the plant’s root system, be porous to allow ample air space for roots to grow, yet retain water and nutrients. PREPARING PLANTS FOR THE HOME ENVIRONMENT (cont.) Growing medium (cont.) Soilless mixes: do not contain garden or mineral soil. Soilless mixes may contain peat moss, coconut fiber , perlite, vermiculite and other inert substances. Advantage: inexpensive, easy for roots to penetrate Disadvantage: do not contain the nutrients plants need Garden soil mixes Potting mixes that contain garden or mineral soil are heavier and provide more stability than soilless mixes. Garden soild are commonly amended with equal volumes of organic matter sand and vermiculite or perlite to improve their characteristics for plant growth. Specialty mixes: Some houseplants require special potting mixes to meet their needs such as orchids and bromeliads. PREPARING PLANTS FOR THE HOME ENVIRONMENT (cont.) Repotting The roots of potted plants are restricted to growing space and can quickly fill that space with roots. They become pot-bound and may need repotting. Pot-bound root system Remove a plant from its container periodically to examine the roots. If there are mostly roots and little soil, the plant is pot-bound and needs repotting. Acclimation Commercial greenhouse and garden centers strive to maintain optimal growing conditions for houseplants. Houseplants need to be gradually weaned from their near-perfect, greenhouse conditions to the less-than- perfect, home environment. When light conditions dramatically change, plants adjust to the new light environment by replacing their leaves. A Boston Fern and a Purple Heart Plant at the library HOUSEPLANT GROWTH AND MAINTENANCE Indoor plant performance changes with the seasons. Plants respond to changes in light, temperature and humidity levels throughout the year. The purpose of a plant will determine whether growth or maintenance is desired. Once a desired size is reached, gardeners should strive to maintain these plants in the home environment. Maintenance occurs when there are sufficient resources to maintain a plant’s current size and condition. Water Improper watering is the leading cause of houseplant problems. watering too much neglect to provide enough water Either leads to weakened plants, more susceptible to disease and insects HOUSEPLANT GROWTH AND MAINTENANCE (cont.) General houseplant watering suggestions: Know the soil moisture requirement Check the moisture level and apply water accordingly Allow tap water to sit for an hour for chlorine to escape Avoid using water that has passed through water softening systems Fertilize only as needed Thoroughly wet the soil with the top-down or bottom-up-method Avoid wetting the foliage or crown of the plant Discard any remaining water that may be in a pot saucer All houseplants should be thoroughly watered where the entire soil volume and root mass is wetted. Two watering methods: Top-down watering Bottom-up watering HOUSEPLANT GROWTH AND MAINTENANCE (cont.) Light Light is one of the most important factors affecting houseplants’ success. Light affects: Dormancy Growth Flowering Leaf coloration Window light changes with the seasons and varies greatly over the course of a year. This light variance explains why some plants cannot endure the strong sunlight that pours through south-facing windows in the summer yet thrive in the same window in the fall and winter. HOUSEPLANT GROWTH AND MAINTENANCE (cont.) Light Variance: South-facing windows receive the most intense light most appropriate for plants requiring high-light intensities plants should be set back several inches form windowpane East-and west-facing windows have roughly two-thirds of the light of south-facing windows work well for plants requiring moderate light levels North-facing windows receive approx one fifth of the light of south facing windows will only accommodate low-light plants are the coolest/do not receive direct sunlight A light meter is the best way to accurately measure light levels both indoors and out. HOUSEPLANT GROWTH AND MAINTENANCE (cont.) Temperature Most foliage houseplants grow best at daytime 70-80 F degrees night 60-68 F degrees Extremes may cause limited growth, foliage damage of loss and even plant death. Humidity Humidity is the amount of water vapor present in the air at a given temperature. Houseplants vary in their humidity needs some require high humidity, some normal home humidity and others require low humidity. To improve humidity levels for all houseplants, cluster plants together on a tray of moist pebbles. HOUSEPLANT GROWTH AND MAINTENANCE (cont.) Fertilization Fertilization needs vary with plant age, growing medium, season and growth objectives. Frequency of feedings can vary dramatically from every two weeks to several months. Most plants do not require fertilizer during maintenance mode in winter months, since decreases in both light levels and temperature result in little to no growth. Synthetic houseplant fertilizers come in many forms – granular, crystalline, concentrated liquid, tablet and spikes. When considering fertilizer applications, it is important to be aware of the growth rate of houseplants. HOUSEPLANT GROWTH AND MAINTENANCE (cont.) Grooming and Cleaning Most houseplants must be occasionally groomed throughout the year. Dust accumulates on leaves interferes with photosynthesis air exchange Dust can be removed from the leaves using a damp cloth and spray Lower leaves may fade and turn brown They may fall off the plant Gardeners should remove these aged leaves Compost or discard them Petals of flowering houseplants will fade and decline over time Faded or brown petals should be removed Compost or discard them HOUSEPLANT PESTS AND PROBLEMS Routine inspection of houseplants can alert home-owners to signs of plant stress Recognize these signs: Too much light – may cause leaves to curl at the tips develop yellow or brown splotches wilt or fade to a lighter color Too little light - may cause straggly growth smaller new leaves bud drop reduced flowering Internodes will be very long and variegated plants may revert to solid green. Above-ground parts and roots can be pruned to maintain plant vigor keep size consistent renew soil annually Root pruning creates room for new root growth HOUSEPLANT PESTS AND PROBLEMS (cont.) Soluble Salts Excess salts from fertilizers and those naturally found in tap water accumulate over time. The white crust that builds up on the pot and growing medium’s surface is from soluble salts. When salt concentrations become too high in the growing medium water is drawn out of the roots causing dehydration and possibly death. Signs of subsequent plant problems include reduced growth, brown leaf tips, dropping of lower leaves, smaller-than normal new groth, dead root tips and wilting. These excess salts can be removed physically and through leaching. If soluble salts are a recurring problem, reduce the amount of fertilizer applied and consider using distilled water. HOUSEPLANT PESTS AND PROBLEMS (cont.) Diseases Houseplants grown under correct cultural conditions have bery few disease problems. Diseases are most often a result