How to raise Catharanthus roseus? What if the leaves turn yellow?

Catharanthus roseus, also known as daily, daily spring, alum flowers, is a perennial herb or semi-shrub plant of Apocynaceae, which is produced all over tropical Africa and has been cultivated in various parts of our country. Catharanthus roseus has a long flowering period and many potted plants for present appreciation. It can also be used as a flower bed and flower border material in summer and autumn, or suitable for planting in parks and courtyards to beautify the environment. How to raise the evergreen flowers? What if the leaves turn yellow?

How to raise Catharanthus roseus?

1. Sunshine

Catharanthus roseus is a light-loving plant, there must be sufficient sunshine during the growing period, the leaves are green and shiny, and the flowers are bright. If you grow in the shade for a long time, the leaves will turn yellow and fall.

2. Soil

Suitable for fertile and well-drained soil, resistant to barren soil, but do not be alkaline. Clayey soil with hardening and poor ventilation results in poor growth of plants, yellowing leaves and no flowering.

3. Temperature

Prefer a warm, slightly dry and sunny environment. The suitable temperature for growth is 18: 24 ℃ from March to July, 13: 18 ℃ from September to March of the following year, and the winter temperature is not lower than 10 ℃.

4. Watering

Catharanthus roseus avoid dampness and fear of waterlogging, basin soil watering should not be too much, too wet affects growth and development. In particular, indoor winter plants should be strictly controlled watering, it is better to dry, otherwise it is easy to freeze. Open field cultivation, midsummer showers, pay attention to timely drainage, so as not to cause the whole area to die by waterlogging.

5. Fertilization

When applying fertilizer, compound fertilizer and liquid fertilizer can be applied alternately every ten days. The bottom of the Catharanthus roseus pot soil should also be covered with a layer of base fertilizer as far as possible to ensure the nutrient content of the pot soil.

6. Diseases and insect pests

Insect pests: Catharanthus roseus plants are poisonous, so they are more resistant to diseases and insect pests. The main diseases in seedling stage are: seedling quenching disease, Botrytis cinerea and so on. In addition, it is necessary to prevent the occurrence of fertilizer damage and drug damage in seedling stage. If it happens, it should be watered with clean water immediately to strengthen ventilation and reduce the harm. Disease: the stem and leaf rot of Catharanthus roseus mainly occurs in the rainy season, and its pathogen is Phytophthora. When the disease is serious, it leads to a large number of deaths, which seriously affects mass production. Chemical control methods: before the rain with 65% good life 600 million 800 times or 1% equivalent Bordeaux solution protection. If the disease is timely sprayed with 72% Kloe 600kg 800 times or 25% Pulex 600kg 800 times, the control effect is better once a week.

8. Pruning

Catharanthus roseus is a herbaceous plant, which is more suitable for potted plants, but it should be careful not to let the plant grow too high, affecting indoor decoration and ornamental, so after surviving in the pot, it is necessary to pick the heart several times to promote multiple branches and more flowering, and the residual flowers must be cut off after flowering.

Second, how to do if the leaves of Catharanthus roseus turn yellow?

1. Poor permeability of soil.

Poor soil permeability is also the reason for the yellowing of Catharanthus roseus leaves. Many people plant flowers with high soil viscosity and poor water permeability. There is no problem with this kind of soil in the short term, but over time, the poor permeability of the soil results in poor breathing in the lower roots of Catharanthus roseus, resulting in frequent yellow leaves and fallen leaves.

Solution: choose sandy soil with good drainage performance to plant, but also pay attention to not watering too much.

2. Overwatering

Catharanthus roseus avoid dampness and fear of waterlogging, basin soil watering should not be too much, otherwise it will affect root breathing and cause old leaves yellow, new leaves yellow.

Solution: strictly control watering, it is better to dry, and pay attention to drainage in rainy season.

3. Excessive fertilization

Many flower friends worry that Catharanthus roseus does not have enough nutrients and blossom, and occasionally put a little fertilizer or something into the potted soil, hoping to absorb more flowers. This way is correct, but the fault lies in the frequency of fertilization, if fertilization is often applied, Catharanthus roseus is difficult to fully absorb, fertilizer remains in the soil, always around the root, resulting in the whole Catharanthus roseus malaise, slow growth, less flowering, petals smaller.

Solution: Catharanthus roseus can be applied alternately by compound fertilizer and liquid fertilizer, and don't apply fertilizer casually at other times. Watering the next day after fertilization promotes the absorption of nutrients.