How to grow potted gladiolus? A complete guide to care methods

The scientific name of gladiolus is Gladiolus grandiflora, also known as sword lily, flat bamboo lily, ten-variety brocade, etc. It is a perennial herbaceous plant of the genus Gladiolus in the iris family, widely cultivated around the world, and an important cut flower. It can be used for flower baskets, bouquets, vase arrangements, etc., and can be used to arrange flower borders and specialized flower beds. Dwarf varieties can be grown in pots for ornamental purposes. Now let's take a look at how to grow potted gladiolus well!

Growth habits of gladiolus

Gladiolus is a plant that likes warmth, but excessively high temperatures are unfavorable for its growth. It is not cold-tolerant. The suitable growth temperature is 20-25°C. The corms can sprout when the soil temperature is above 5°C. It is a typical long-day plant. Long days are beneficial for flower bud differentiation. Insufficient light will reduce the number of flowers, but after flower bud differentiation, short days are beneficial for bud formation and earlier flowering. The bulbs of summer-flowering varieties must be stored indoors over winter, and the room temperature must not be lower than 0°C. The cultivation soil should preferably be fertile sandy loam, with a pH value not exceeding 7. It especially likes fertilizer. Phosphate fertilizer can improve flower quality, and potassium fertilizer helps improve corm quality and the number of cormels.

Propagation methods of gladiolus

1. Corm division: After 1 year of cultivation, each mother corm of gladiolus will produce 1-2 commercial corms and many cormels. Medium and large corms are planted by the furrow dibbling method, with the furrow depth about 3 times the corm diameter, and the plant spacing flexibly determined according to corm size. Small corms are planted by the furrow broadcasting method, and cormels are mostly planted by direct broadcasting. Before planting, apply sufficient base fertilizer, but note that the fertilizer must not directly contact the corms. After sowing, pay attention to water management, and do not water before emergence unless the soil is dry.

2. Corm cutting: For some rare varieties of gladiolus that need rapid expansion of propagation coefficient, plump and full commercial corms can be cut into 2-4 pieces, each piece must retain part of the basal plate and a complete plump bud, and these are used for cormel propagation. To prevent the seed corms from rotting, the cut surfaces should be smeared with charcoal powder or plant ash and planted immediately.

3. Tissue culture: Tissue culture propagation can rejuvenate conventional cultivated varieties. Because long-term asexual propagation causes quite serious variety mixing and degeneration, regular tissue culture must be carried out for virus elimination and rejuvenation. Petals and lateral buds can both be used as explants. After disinfection and inoculation, they can be placed at 25°C and 2000 lux for culture, and seedlings are obtained through induction, subculture, and rooting culture. Continued culture of the seedlings can produce test-tube cormels, and after hardening and two years of planting, the test-tube corms grow into mother corms.

How to grow potted gladiolus?

1. Temperature: Gladiolus has relatively high temperature requirements. The optimum temperature is around 20°C. When the temperature is below 10°C, it begins to stop growing, and when it is below 3°C, it may suffer frost injury and die.

2. Light: Gladiolus is a light-loving plant and requires relatively long sunshine, so during growth it needs long-term sunlight, otherwise pest or disease problems may occur.

3. Humidity: The humidity requirements of gladiolus are actually the same as those of some other plants such as bromeliads and frangipani. As long as a certain humidity is maintained, and in hot summer remember to water the leaves more to keep them moist.

4. Soil: Gladiolus prefers soil rich in organic matter and relatively rich in nutrients. Generally, maintaining ventilation and good drainage is sufficient.

5. Watering: Gladiolus is a bulbous plant, and it is relatively strict about water and fertilizer control. Before planting in pots, the soil needs to be moistened to some extent. The general requirement is not to water unless the soil is dry, and to water as soon as it dries.

6. Fertilization: Fertilization of gladiolus is also very important. Generally, fertilization begins after the leaves first appear. During the flower bud stage, remember not to use nitrogen fertilizer; what is needed for flowering at this time is phosphate fertilizer. Also carry out weeding frequently.

Pest and disease control of gladiolus

1. Mosaic disease

[Symptoms] It infects leaves and also infects parts such as flowers. In the early stage of the disease, chlorotic angular spots and round spots appear on the leaves. Because spot expansion is restricted by leaf veins, they are mostly polygonal, and finally turn brown. Diseased leaves become yellowed and twisted. Affected plants are dwarfed and have short flower spikes, and severely affected plants cannot produce flower spikes. In early summer, symptoms on new leaves are especially obvious, while in midsummer symptoms are not obvious, with a phenomenon of symptom masking.

[Control] Strengthen quarantine to control disease occurrence. Test corms, select virus-free corms for planting, and uniformly destroy virus-carrying corms to reduce reinfection of flowers. Promptly remove diseased plants from flower beds to prevent mutual infection. When disease occurs, spray leaves with 58% mancozeb wettable powder 500 times solution, or 75% chlorothalonil wettable powder, or 50% carbendazim wettable powder 1000 times solution, spraying once every 7 days, generally 3-4 sprays are sufficient.

2. Dry rot

[Symptoms] It harms the corms, leaves, flowers, and roots of the plant. When the plant becomes diseased, the tips of the outer leaves first turn yellow, then it spreads to the inner leaves, and finally they wither.

[Control] Try to avoid continuous cropping in the planting flower beds, do not apply excessive nitrogen fertilizer, and appropriately increase the use of phosphate and potassium fertilizers. Before planting, corms can be soaked in 50% carbendazim 500 times solution for 30 minutes. In the early stage of plant disease, spray the leaf surface with 50% zineb 1000 times solution once every 7 days, generally spraying 3 times.

3. Leaf spot

[Symptoms] The pathogen can infect leaves and corms. After leaf infection, small brown spots appear, then gradually expand, and the color gradually deepens, finally causing the leaves to wither. After corm infection, the plants that grow are dwarfed and may even fail to bloom.

[Control] Implement crop rotation. Severely affected areas must be rotated to reduce disease-causing seedlings. After harvest, corms should be dried and stored dry to prevent rot. Before planting, they can be disinfected with 50% thiram and then sown. For chemical control, spray with 75% chlorothalonil 800 times solution or treat with 65% zineb.

4. Scab

[Symptoms] It damages corms and sometimes also leaves. After corm infection, water-soaked round lesions appear, and the color gradually deepens from gray to dark brown. The lesion edges are raised and the centers are sunken. After leaf infection, water-soaked soft rot occurs.

[Control] Use disease-resistant cultivation, choose a dry and well-ventilated environment, pay attention to drainage, carry out crop rotation, and maintain field sanitation. This disease can only be prevented, not cured, and there is no specific drug.

5. Fusarium wilt

[Symptoms] It occurs on corms and sometimes also infects leaves and flowers. In the early stage of disease, small reddish-brown spots appear, then gradually expand, become sunken and shrunken, and even rot, after which white thread-like structures grow. After infected corms are sown, in mild cases growth is poor and flowering is deformed; in severe cases they cannot sprout or the seedlings die.

[Control] Double selection and disinfection of corms. After harvest, grade and remove diseased corms. Soak seed corms in 0.5% formalin solution for 2h, wash with warm water, dry, and refrigerate until the next spring. At sowing, carry out a second selection and disinfect with 5% carbendazim 500 times solution before sowing. Avoid continuous cropping.

6. Gray mold

[Symptoms] It often occurs on leaves and petals. In the early stage of disease, small grayish-brown spots often appear, then gradually expand, and gray mold appears on the surface of the lesions.

[Control] Store corms reasonably, keep the environment dry, keep the cultivation environment ventilated and well-lit with good drainage. For chemical control, spraying with 80% zineb wettable powder 500-700 times solution has a relatively good effect.

7. Thrips

[Symptoms] They bite and feed on the leaves, stems, and flowers of the plant, causing leaf discoloration and leaving grayish-white dot-like feeding marks and oviposition marks on the corolla, resulting in curled petals.

[Control] Spray with 40% dimethoate emulsifiable concentrate 1000 times solution or 80% dichlorvos emulsifiable concentrate 300 times solution for control.