Dahlias are a genus of bushy, tuberous, herbaceous perennial plants native to Mexico. They are a popular garden flower, grown for their showy, colorful blooms. Dahlias come in a variety of sizes, shapes, and colors, ranging from small, single-flowered types to large, double-flowered varieties. They are typically grown from tubers, and can reach heights of up to 4 feet. Dahlias require full sun and well-drained soil for optimal growth. They are easy to care for, and are generally pest and disease free.
Planning Your Garden With Dahlia
As you plan your garden, it's important to think about the spacing, size, light, and nutrient requirements of all of your plant and how they'll grow together.
Some plants require more water than others, while other plants require dry soil. At the same time, some plants prefer full sun, and other plants need the shade to survive.
By studying what each plant requires and planning ahead where all of your plants will grow best, you can optimize your garden space.
| Life Cycle | Dahlia is a perennial. |
| USDA Zone | Dahlias are hardy in USDA Zones 7-10. |
| Cold Tolerance | Dahlias are generally hardy in USDA zones 8-11, meaning they can tolerate temperatures as low as 32. |
| Days to harvest | The minimum number of days to harvest for dahlia is 70-90 days. |
| Average size | The average size of a full grown dahlia plant is between 2 and 4 feet tall and 1 to 2 feet wide. |
| Spacing requirements | The best spacing for growing dahlias is 18-24 inches apart. |
| Sun tolerance | Dahlias are generally considered to be sun-loving plants and can tolerate full sun. However, they do need some protection from the intense afternoon sun in areas with hot climates. |
| Shade tolerance | Dahlias are considered to be moderately shade tolerant, meaning they can tolerate some shade, but they will do best in full sun. |
| Water requirements | Dahlias need a minimum of 1 inch of water per week. They should be watered deeply and evenly, preferably in the morning, to ensure the water penetrates the soil and reaches the roots. During periods of extreme heat, they may need to be watered more frequently. |
| Fertilizer | The amount of fertilizer you should use when growing dahlia depends on the type of fertilizer you are using and the soil conditions. Generally, a balanced fertilizer with an NPK ratio of 10-10-10 should be applied at a rate of 1-2 pounds per 100 square feet of soil. If you are using a slow-release fertilizer, apply it at a rate of 1-2 tablespoons per plant. |
| Soil pH | The optimum pH for growing dahlia is 6.0 to 6.5. |
Why Dahlia is Popular
People like to grow dahlia because they are easy to grow, come in a variety of colors and sizes, and they produce long-lasting blooms that can be used in cut flower arrangements. Dahlias are also known for their ability to attract pollinators like butterflies and hummingbirds.
Companion Plants For Dahlia
Companion planting is a great way to maximize your garden space and get the most out of your plants. By planting certain plants together, you can help each other thrive. In some cases, you can even help each other repel pests.
Popular companion plants for dahlia include:
Common Pests For Dahlia
Plant pests are a common problem for gardeners. By understanding what pests are common for your plants, you can take steps to prevent them from damaging your plants.
When you grow dahlia, keep an eye out for these common pests:
- snails
- thrips
- slugs
- aphids
- whiteflies
- spider mites
USDA Zones
USDA zones are a popular way of determining which plants can grow in your area. Zones tell you when your average first and last frost date are, as well as how cold you can expect it to get in the winter.
Our site works best if you choose your zone from the list below. If you do not know your USDA zone, then you can use our zone map.
