Here are a few growing tips to keep in mind when growing your beautiful dahlias.
-These notes are from the American Dahlia Society-
Fundamentals of Growing Dahlias
Dahlias are easy plants to grow and yield beautiful blooms from mid-summer through fall. In many respects, “dahlia culture” is similar to “tomato culture.” If you can grow tomatoes in your garden, you can successfully grow dahlias. The following notes will help you to add spectacular blooms and brilliant color to your garden!
When to Plant
Your tubers can go directly into the ground in the spring when the ground has warmed and there is little chance of frost. One good guideline is to plant in the same time frame as you would a tomato. If you want blooms as early as possible, you can start the tubers indoors in good light about a month before planting time. You will then have a small plant ready at planting time. Dahlias can be planted as late as mid-June in most parts of the country.
Where to Plant
Dahlias require a site with good drainage and partial to full sun. Pots are also increasingly popular way to grow Dahlias.
How to Plant
Most dahlias need to be staked and you may want to plant a sturdy stake before you plant the Dahlia. If you put the stake into the ground after the plant is growing, take care to avoid damaging the tuber or the root system. Tomato cages can also be a simple approach to staking.
Put the tuber in a hole several inches deep with the “eye” on the tuber facing up. The eye is the point on the shoulder, or crown, of the tuber from which the plant grows.
If you are planting a number of dahlias in the same location, they should be separated by about 2 feet to give each plant room to grow.
Suburban shrubbery and gardens are increasingly susceptible to damage by deer. The good news for Dahlias is that they are low on the deer’s list of favorite foods. While Dahlias are not “deer proof,” they are considered to be so in some parts of the country – probably those areas where deer find enough other plants they prefer to eat.
Watering and Fertilizing
Young Dahlia plants do not need a lot of water; in fact, excessive water can lead to rotting of the plant. For larger plants, a good rule of thumb is to water if the rainfall is less than one inch in seven days. Pots require more regular watering.
The best strategy for fertilizing is to begin with a soil test to determine pH and the specific soil needs. Lacking that information, the plants will generally benefit from regular treatments with a water soluble or granular fertilizer. Traditional wisdom for dahlias is to treat with a high nitrogen fertilizer through the middle of the season but minimize nitrogen at the end of the season.
Maintaining Your Plants
There is a substantial regimen that can be used for maintaining plants for show blooms. For the simple enjoyment of spectacular dahlias in your garden, there are two relatively simple actions that will enhance the appearance of the plant. First is tying the plant to the stake several times as it grows. The first tie should secure the lower portion of the plant’s stalk to the stake. Subsequent ties should secure the branches. A simple alternative to tying is to use a tomato cage to support the plant. Then, no tying may be required.
Second is disbudding. Remove the outer two buds from the three that develop at the end of each branch. While that reduces the total number of flowers, many flowers remain and those show up well on the plant. If all three buds are left on the stem, the blooms will tend to be covered up and can be lost in the plant. You can also remove some of the shoots that form along the branch to have stems that can be used in tall vases for elegant bouquets.