Blue Spruce vs Calla Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Blue Spruce
Picea pungens
The Blue Spruce is a coniferous evergreen tree known for its distinctive blue-green needles and pyramidal shape. It is a large tree, typically growing outdoors to heights of 50-75 feet. Its needles are stiff and sharp, radiating in all directions from the branches. Cones are light brown and papery. It's primarily grown as an ornamental tree for its striking color and symmetrical form. It is not naturally an indoor plant and will struggle significantly indoors.
Calla
Zantedeschia aethiopica
Zantedeschia aethiopica, commonly known as Calla Lily, is a rhizomatous herbaceous perennial prized for its elegant, trumpet-shaped spathes (modified leaves) that surround a central spadix. While often called a lily, it is not a true lily. It grows from rhizomes, producing large, arrow-shaped, glossy green leaves. It is primarily an outdoor plant, thriving in moist conditions. People grow it for its striking flowers, often used in bouquets and floral arrangements. It can be grown indoors, but requires specific conditions to thrive and may not flower as readily as outdoors.
Quick Plant Comparison
| Feature | Blue Spruce | Calla |
|---|---|---|
| Light | Full sun (at least 6 hours of direct sunlight daily) | Bright, indirect light to full sun outdoors. Indoors, provide bright indirect light, ideally near an east- or west-facing window. |
| Watering | Water deeply at planting and then as needed during dry periods, typically every 2-4 weeks once established. | Every 3-7 days during the growing season, less frequently in winter. |
| Humidity | 30-50% | 40-60% |
| Temperature | 10-24°C | 18-24°C |
| Care Level | Expert | Moderate |
| Growth Rate | Slow To Moderate | Moderate |
| Max Height | Not applicable indoors. Outdoors: 15-23 meters | Indoors: 0.6-1 meter |
| Pet Safety | ❌ Toxic To Pets | ❌ Toxic To Pets |
| Soil | Well-draining, slightly acidic soil. Avoid heavy clay soils. | Well-draining potting mix rich in organic matter. A mix of peat moss, perlite, and compost is suitable. |
| Beginner Friendly | ❌ No | With Caution |
| Weekly Maintenance | 15 minutes monthly (mostly inspection for pests/disease) | 10 minutes weekly |
🔬 Botanical Information — Comparing These Plants
Blue Spruce
| Scientific Name | Picea pungens |
|---|---|
| Family | Pinaceae |
| Native To | Rocky Mountains of the United States |
| Also Known As | Colorado Blue Spruce, Blue Spruce |
| Leaves | The needles are stiff, sharp, and approximately 1-inch long. They are four-sided and radiate in all directions from the branches. The color ranges from blue-green to silvery-blue, depending on the individual tree and the amount of wax coating on the needles. |
| Flowers | Blue Spruce trees produce small, inconspicuous flowers in the spring. These are not typically noticeable and are not the primary ornamental feature of the tree. It does not flower indoors. |
Calla
| Scientific Name | Zantedeschia aethiopica |
|---|---|
| Family | Araceae |
| Native To | South Africa |
| Also Known As | Calla Lily, Arum Lily, Trumpet Lily |
| Leaves | Large, arrow-shaped, glossy green leaves. The leaves can be up to 45 cm long and 25 cm wide. Some varieties have speckled or variegated leaves. |
| Flowers | Can flower indoors with proper care, but more reliably flowers outdoors. The 'flower' is a modified leaf called a spathe, which is typically white, but can also be pink, yellow, orange, or purple. The spadix, the yellow spike in the center, is where the true flowers are located. |
📏 Size & Growth — Plant Comparison
Blue Spruce
Calla
🌱 Propagation — Comparing Plant Growth
Blue Spruce
Methods: Seed, Cuttings, Grafting
Difficulty: Difficult
Tips: Propagation from seed is slow and requires stratification. Cuttings are difficult to root and grafting is the most reliable method, but requires specialized skills.
Calla
Methods: Division, Seed
Difficulty: Moderate
Tips: Divide rhizomes in early spring before new growth begins. Ensure each division has at least one eye (bud). Plant divisions in well-draining soil and keep moist. Seed propagation is possible but slower.
✨ Benefits & Features — Comparing Plant Value
Blue Spruce
The Blue Spruce is known for its striking blue-green needles, which are sharper and more rigid than those of other spruce species. The color intensity can vary among individual trees, with some exhibiting a more pronounced blue hue.
- ✓ Provides year-round visual interest
- ✓ Offers shelter and nesting sites for birds
- ✓ Can be used as a windbreak
- ✓ Relatively low-maintenance once established
- ✓ Increases property value.
- ⚠️ Toxic to pets
Calla
The Calla Lily is not a true lily, but a rhizomatous perennial with a unique spathe and spadix flower structure. Its elegant, trumpet-shaped flowers make it a popular choice for bouquets and floral arrangements. It requires a dormant period in winter to promote flowering in the following season.
- ✓ Aesthetically pleasing flowers.
- ✓ Can be used for cut flower arrangements.
- ✓ Adds a touch of elegance to any room.
- ✓ Can improve mood and reduce stress.
- ✓ Provides a sense of accomplishment through successful care.
- ⚠️ Toxic to pets
📅 Maintenance Schedule — Plant Care Comparison
Blue Spruce
Calla
🌞 Light Requirements
Blue Spruce
Full sun (at least 6 hours of direct sunlight daily)
Low light tolerant: ❌ No
Calla
Bright, indirect light to full sun outdoors. Indoors, provide bright indirect light, ideally near an east- or west-facing window.
Low light tolerant: ❌ No
💧 Watering Needs
Blue Spruce
Water deeply when planting and during dry periods, especially when young. Established trees are relatively drought-tolerant. Overwatering can lead to root rot, so ensure well-draining soil. Signs of underwatering include browning needles and drooping branches. Signs of overwatering include yellowing needles and soggy soil.
Calla
Keep the soil consistently moist, especially during the growing season. Water thoroughly when the top inch of soil feels dry. Reduce watering in the dormant period. Overwatering can lead to rhizome rot, indicated by yellowing leaves and a foul odor. Underwatering results in wilting and browning leaf tips.
🌡️ Temperature & Humidity
Blue Spruce
Temperature: 10-24°C
Humidity: 30-50%
Calla
Temperature: 18-24°C
Humidity: 40-60%
🤔 Which Plant Is Right For You?
Blue Spruce
Picea pungensLandowners with large properties seeking a striking ornamental evergreen tree.
✅ Choose This Plant If...
- You have a large outdoor space and want a striking evergreen tree
- You live in a climate with cold winters and full sun
- You want to attract birds and other wildlife to your property
- You appreciate the unique blue-green color of the needles
- You are looking for a relatively low-maintenance tree once established.
❌ Skip This Plant If...
- You live in an area with hot, humid summers
- You have limited space or are looking for an indoor plant
- You have pets that may ingest the needles
- You have poorly draining soil
- You dislike sharp needles.
Calla
Zantedeschia aethiopicaExperienced plant enthusiasts seeking a flowering plant with elegant blooms, willing to provide specific care requirements.
✅ Choose This Plant If...
- You appreciate elegant, trumpet-shaped flowers.
- You can provide bright, indirect light and consistent moisture.
- You are willing to provide a dormant period in winter.
- You are experienced with plant care and can address potential problems.
- You want a plant that can be used for cut flower arrangements.
❌ Skip This Plant If...
- You have pets that may ingest the plant.
- You cannot provide bright light or consistent moisture.
- You are a beginner plant owner.
- You prefer low-maintenance plants.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Blue Spruce is rated Expert care level, while Calla is Moderate.
Blue Spruce has slow to moderate growth, while Calla grows moderate.
💡 Pro Tips For Comparing These Plants
Blue Spruce Care Tips
Blue Spruce is an outdoor tree and is not suitable for indoor growing. It requires full sun, well-draining soil, and cold temperatures to thrive. Indoor attempts will likely result in a stressed and unhealthy plant.
- Plant in well-draining soil to prevent root rot
- Water deeply during dry periods, especially when young
- Mulch around the base of the tree to retain moisture
- Protect young trees from heavy snow and ice
- Monitor for pests and diseases regularly.
Calla Care Tips
Calla Lilies require bright light and consistent moisture. They can be grown indoors, but may not flower as readily as outdoors. Ensure good drainage to prevent rhizome rot. Toxicity to pets is a significant concern. Requires a dormant period in winter.
- Provide a dormant period in winter by reducing watering and keeping the plant in a cool location.
- Ensure good drainage to prevent rhizome rot.
- Fertilize regularly during the growing season to promote flowering.
- Monitor for pests and diseases and treat promptly.
- Provide bright, indirect light for optimal growth and flowering.
⚠️ Common Problems & Solutions — Plant Care Comparison
Blue Spruce
Calla
❓ Frequently Asked Questions — Comparing These Plants
Blue Spruce
What are the light requirements for Blue Spruce?
Blue Spruce requires bright, indirect light to thrive indoors. Insufficient light can lead to leggy growth and faded coloration. A south-facing window with sheer curtains is ideal, providing ample light without direct sun exposure, which can scorch the needles. Rotate the plant regularly to ensure even light distribution on all sides. If natural light is limited, supplement with grow lights to maintain healthy growth. Proper lighting is crucial for the development of the characteristic blue hue of the needles. Monitor the plant for signs of light stress, such as yellowing or browning needles, and adjust its placement accordingly.
How do I care for Blue Spruce?
Blue Spruce thrives indoors with proper care. Provide bright, indirect light, preferably near a south-facing window. Water thoroughly when the top inch of soil is dry, ensuring good drainage to prevent root rot. Maintain moderate humidity levels, especially during dry winter months. Fertilize sparingly during the growing season (spring and summer) with a balanced liquid fertilizer. Prune lightly to maintain shape and remove any dead or yellowing needles. Repot every 2-3 years into a slightly larger pot with well-draining soil. Ensure proper air circulation to prevent fungal diseases. Monitor for pests like spider mites and treat promptly if detected. Provide a stable environment with consistent temperature and humidity levels. Avoid placing near heat vents or drafts.
How do I propagate Blue Spruce?
Blue Spruce can be propagated through stem cuttings or air layering, though success rates can be low indoors. For stem cuttings, take 4-6 inch cuttings from new growth in late winter or early spring. Remove the lower needles and dip the cut end in rooting hormone. Plant the cutting in a well-draining potting mix and keep it consistently moist, but not waterlogged. Cover with a plastic bag to maintain humidity. For air layering, make a small incision on a branch and wrap it with moist sphagnum moss. Cover the moss with plastic wrap and secure it with tape. Keep the moss moist. Once roots develop, cut the branch below the rooted area and pot it in soil. Be patient, as rooting can take several months.
Calla
What are the light requirements for Calla?
Calla lilies thrive in bright, indirect light. Direct sunlight can scorch their leaves, so avoid placing them in south-facing windows without some form of shading. An east- or west-facing window is ideal, providing ample light without the intensity of direct sun. If you notice the leaves becoming pale or the plant failing to bloom, it may not be receiving enough light. In such cases, consider supplementing with artificial grow lights. During the darker winter months, supplemental lighting is particularly beneficial to maintain healthy growth and encourage future blooms. Ensure the light is diffused to prevent leaf burn. Regular rotation of the plant ensures all sides receive adequate light, preventing uneven growth.
How do I care for Calla?
Calla lilies require bright, indirect light for optimal growth and blooming. Water thoroughly when the top inch of soil feels dry, ensuring proper drainage to prevent root rot. During the growing season (spring and summer), fertilize every 2-4 weeks with a balanced liquid fertilizer diluted to half strength to encourage flowering. Reduce watering and fertilization during the dormant period in fall and winter. Maintain a humidity level of 50-60%. Repot annually in spring using well-draining potting mix. Remove spent flowers to encourage more blooms. Monitor for pests like aphids and spider mites, and treat promptly if detected. Provide support for taller varieties to prevent them from bending. Rotate the plant regularly to ensure even growth and prevent leaning towards the light source. Protect from frost and freezing temperatures.
How do I propagate Calla?
Calla lilies can be propagated by division, stem cuttings (though less common), and keiki (small plantlets that sometimes form on the plant).
Last updated: April 30, 2026 — Plant care data reviewed and verified by our editorial team.