Dahlia, also known as Dali flower, Geranium peony, dahlia and sweet potato flower, is a perennial herb with huge club like roots.
Dahlia originated in Mexico. Mexicans regard it as a symbol of generosity and richness, so they regard it as the national flower.
Dahlia likes light but can't bear shade. When the temperature is below 30 ℃, try to take full sunlight, so that the plants are strong and the flowers are large and full. When the temperature rises above 35 ℃, avoid exposure to the sun.
Dahlia is suitable for cultivation in loose and fertile sand or humus soil with good drainage, which is drought and waterlogging resistant.
Dahlia is sensitive to water. Leaves will wilt when water is scarce, and roots will rot when water is too much. It is necessary to keep the soil moist but not seeper or sticky. Pay attention to drainage in rainy days.
For fertilization, the thin compound liquid fertilizer shall be applied every 10-15 days from the beginning of seedlings, and the P-K liquid fertilizer shall be applied every 7-10 days after budding, and the fertilizer shall not be applied when the flower bud is colored and the temperature is high.
The amount of fertilizer should be determined according to the growth of the plant. The light and barren leaves lack nitrogen fertilizer. The scorching edge or yellow tip of the leaves are excessive fertilizer. The thick and dark green leaves indicate that the amount of fertilizer is appropriate.
Dahlia likes a cool climate. The temperature requirement is not strict during the growing period. It can grow at 8-35 ℃, and it is suitable at 15-25 ℃.
In the last ten days of September, dahlia blossomed the largest, brightest and most prosperous, but it was not frost resistant, and its stems and leaves withered immediately after frost.
Dahlia can be divided into tall varieties and short varieties. The highest one can grow to 4 meters, and the shorter one is more than 20cm.
Then, if you are in the balcony or indoor maintenance, then the gallery series, water lily shape, cactus palm shape series are more suitable for you, and the varieties with theoretical height more than 70cm are not suitable.
If you are in the courtyard maintenance, you can choose umbrella series, Anemone series and decorative flower series.
When the seedling grows to 6-8 cm, it begins to remove the heart. The main stem retains 4 leaves. When the lateral branches grow out, it leaves 2 leaves to remove the heart.
Large varieties adopt the unique plastic treatment, that is, to retain the top bud, remove all the axillary buds, so that the nutrition is concentrated, and form the single Dahlia with low plant and large flower type.
The medium-sized variety adopts four plastic plants, which can remove the heart of the seedling, keep two nodes at the base, and form four lateral branches, each of which has a terminal bud, so that it can become a 4-stem 4-flower potted dahlia.
At the second and third nodes of the bifurcated part of the mother branch after flowering, cut off the upper branches, apply a little thin fertilizer after pruning, and after a week or two, the new buds will sprout between the nodes, and when the new buds grow up, it can realize the second flowering.
After the branches and leaves wither, dig out the seed ball, put it in the shade to dry, then bury it in the sand, put it in the indoor place above 7 ℃ but not too hot, and let it sleep naturally;
It can be planted at about 15 ℃ next spring.
In the south of China, there is no pilling in winter. Stop watering below 10 ℃, or the ball will rot.
