Philodendrons, known for their lush foliage, can thrive outdoors in suitable environments. While often seen as indoor plants, certain varieties adapt well to outdoor conditions, adding a vibrant touch to gardens and patios. Growing philodendrons outside requires understanding their specific needs and local climate.
Understanding Outdoor Suitability
Many philodendron species are tropical and sensitive to cold. However, some varieties tolerate outdoor living, flourishing as garden perennials in warmer climates with beautiful, leathery, glossy leaves.
Selecting the right philodendron type is key. Arborescent, or tree-like, philodendrons like Thaumatophyllum bipinnatifidum (formerly Philodendron selloum) and Philodendron xanadu are hardy and self-supporting, suitable for landscape planting in warmer zones. Vining varieties such as Philodendron hederaceum (Heartleaf Philodendron) are also adaptable, often used in hanging baskets or trained to climb. Other types include Philodendron gloriosum and ‘Prince of Orange’, offering unique leaf shapes and colors.
Climate is paramount for outdoor philodendrons. These tropical plants require temperatures that do not consistently drop below 55°F (13°C), with an ideal range of 65°F to 85°F (18°C to 29°C). Frost-free regions, typically USDA Hardiness Zones 9 to 11, are most conducive to year-round outdoor growth. Outside these zones, philodendrons can be enjoyed outdoors during warmer months but need protection or relocation indoors when temperatures fall.
Essential Outdoor Care
Proper light placement is vital for outdoor philodendrons. Most varieties prefer bright, indirect sunlight or dappled shade, mimicking their natural forest habitat. Direct, intense afternoon sun can scorch and discolor leaves, so morning sun and afternoon shade is often ideal. Observe the plant’s reaction to light to adjust placement for optimal health.
Well-draining, rich, and airy soil is essential for outdoor philodendrons. Incorporating organic matter like peat moss or coco coir enhances soil structure, ensuring moisture retention without waterlogging. Good aeration prevents root rot, and a slightly acidic to neutral soil pH (5.5-6.5) is preferred. For in-ground planting, a raised bed or slight slope can further improve drainage.
Outdoor philodendron watering needs differ from indoor care due to rainfall and temperature. Keep the soil consistently moist but not soggy, allowing the top inch or two to dry between waterings. Deep watering is more effective than frequent shallow watering, encouraging stronger root development. Adjust frequency based on weather; hotter, drier periods need more watering, while cooler or rainy spells require less.
Temperature and humidity affect outdoor philodendron health. Consistent humidity levels, ideally around 60% or higher, benefit their growth. In drier climates, grouping plants can create a localized microclimate with higher humidity. While misting offers a temporary boost, it can sometimes lead to fungal issues if leaves remain wet.
Fertilization supports robust growth. During the active growing season (spring and summer), apply a balanced liquid fertilizer or slow-release granular food every four to six weeks. Avoid over-fertilization, which can lead to nutrient burn or excessive foliage growth. Reduce or cease fertilization during cooler, dormant months.
Protecting Your Outdoor Philodendron
Protecting outdoor philodendrons from cold and frost is essential in many regions. Freezing temperatures are detrimental, and temperatures below 55°F (13°C) can cause damage. For potted plants, move them indoors before the first frost. In-ground plants can be protected by covering them with frost cloths, blankets, or sheets, ensuring the cover extends to the ground to trap warmth. A thick layer of mulch around the base insulates roots from cold.
Preventing pests and diseases is ongoing for outdoor philodendrons. Common pests include:
Aphids
Mealybugs
Spider mites
Scale insects
Regular inspection of leaves, especially the undersides, helps early detection. Good air circulation and proper care reduce susceptibility. For initial infestations, a strong water spray can dislodge pests, while organic options like insecticidal soap or neem oil are effective.
Troubleshooting Outdoor Issues
Leaf discoloration often signals underlying issues. Yellowing leaves indicate overwatering, especially if accompanied by drooping or mushy textures. Crispy brown tips or edges suggest underwatering or low humidity. Sunburn from excessive direct light causes white or brown blotches. Addressing watering habits, adjusting light, or improving humidity can resolve these symptoms.
Stunted growth may stem from several factors. Inadequate light, particularly too much shade, can result in leggy growth and reduced vigor. Poor soil quality, lacking nutrients or with insufficient drainage, can hinder development. A root-bound plant will also exhibit slowed growth. Providing appropriate light, enriching the soil with organic matter, and ensuring proper pot size encourages healthier growth.
Pest infestations can become more pronounced outdoors, requiring active management. Visible insects, sticky residue (honeydew), or distorted new growth signal infestation. Aphids are small, pear-shaped bugs; mealybugs resemble cottony masses; and spider mites create fine webbing and tiny pinholes on leaves. For active infestations, wipe leaves with a damp cloth or apply insecticidal soap to eliminate pests. Consistent monitoring and prompt action prevent widespread damage.