Dahlias are rhizomes native to the mountains of Mexico and Colombia. They perform best in cool, humid climates during the summer months. They should be watered, cut and set aside for the winter as they are very delicate flowers.
Steps
Part 1 of 4: Prepare the Dahlias
Step 1. Growth period must be at least 120 days
You cannot plant dahlias until the soil in the garden reaches 16 ° C, so the suitable period is between April and June, depending on where you live.
- Check here the hardness of the soil where you live
- Dahlias grow best where they don't need to be taken out of the earth for the winter. They can also be grown in colder areas as long as the summers are long and sunny.
Step 2. Decide whether to plant rhizomes to be able to cut flowers or to keep them in the garden
If you want to mix them with other flowers, choose small to medium varieties so they won't interfere too much with other plants.
Step 3. Consider planting a row of large dahlias
They love the morning sun and plenty of space.
Step 4. Buy rhizomes that are not too dark
You must cut off any rotten parts before burying them. Place them in sand or Styrofoam packages until you are ready to bury them.
Step 5. Enhance the garden with loose soil such as sphagnum moss or sand
Dahlias also appreciate a slightly acidic pH, between 6, 5 and 7. Top up the soil in a well-drained part of the garden.
Avoid using bagged compost that has been pre-treated for weeds
Step 6. Choose a location with at least 6 hours of daylight per day
These plants prefer morning sun and benefit from shade during afternoon heat spikes.
Part 2 of 4: Planting the Dahlias
Step 1. Wait for the soil to warm to 16 ° C
You can bury the rhizomes about the same time as the tomatoes.
Step 2. Dig about 15-20cm to bury the dahlias
The large ones need to be planted 46-61 cm apart. Throw a handful of ox blood into the pit for a first fertilizer.
Smaller dahlias can be planted close together, at a distance of about 23-30 cm
Step 3. Check that the rhizomes are facing upwards
Cover them with soil. Pile about 6 inches of soil to cover.
Step 4. Don't water until you see them sprout
If the soil is wet, the rhizomes will rot easily.
If you live in an arid climate, you can moisten the soil slightly before planting
Step 5. Set up a sprinkler to water your dahlias after they take root
They should be watered for 30 minutes at a time, two or three times a week. The flow must be gentle and the water must be fully absorbed.
- The water should be about 10 cm deep.
- In hotter, drier climates you may need to water daily.
Step 6. Place baits in the garden for snails and snails as soon as you plant the rhizomes
Snails in particular are fond of small and growing dahlias.
Step 7. If you have planted dahlias with large inflorescences, put on a brace
They will have to lean on something when they grow up. You can tie them to braces or pegs with nylon thread or garden tape.
Part 3 of 4: Treating the Dahlias
Step 1. Fertilize something low in nitrogen once a month when the dahlias are 5-10cm tall
Avoid over-fertilizing as dahlias are sensitive to this too.
Also avoid fertilizing when the season is in full swing
Step 2. Find and trim the final bud when the plant reaches 7.5 to 10cm tall
This is usually the point below the second group of leaves. The plant will divide and create more buds.
Step 3. Cut the flowers at the base of the stem when they are in full bloom
Wait until the stem is at least as long as your wrist to elbow. The buds are in groups of 3 and you can remove the left and right ones for a larger central one.
- Place the cut flowers in hot water. Then let them cool for the next hour. So they should last for 4-6 days.
- Cut the flowers in the morning for best results.
Step 4. Top the withered flowers and cut them regularly throughout the season to help the plant grow and develop other buds
Step 5. Check for aphids and spider mites
You can spray the plants with insecticidal soap to discourage them.
Part 4 of 4: Resting
Step 1. Wait for the first frost to remove the rhizomes
The leaves will begin to blacken when it gets cold. Wait several days for the rhizomes to cool.
Step 2. Cut the stems 6 inches above the ground and mulch
Make sure the mulch layer is thick to insulate the rhizomes well during the winter.
Dig up rhizomes if you live in cold climates
Step 3. Use a shovel if you need to take them out to rest over the winter
This procedure is used to prevent the cold from dying the plants in colder climates.
Step 4. Cut the stem 15 cm from the base
Rinse the rhizomes to remove the soil and allow to dry.
Step 5. Line a box with newspapers
Put the rhizomes in the box but arrange them so they don't touch each other. Pour sand, sphagnum moss, or packet styrofoam between the rhizomes.
