How to Grow Potted Canna Lilies? A Detailed Guide to the Latest Cultivation Methods
The canna lily is robust and highly adaptable, preferring sunny, warm and hot environmental conditions, and is also fairly cold-tolerant. It is not demanding about soil and can grow in all kinds of soil, but grows best in deep, fertile soil. Its optimum growth temperature is higher than that of most flowers, at 25-30°C. Below, the editor of Qiannong Network will introduce the cultivation methods for potted canna lilies!
For potted canna lilies, dwarf varieties are preferable. The soil is generally a mix of leaf mold, vegetable garden soil and rice husk ash in a 1:1.5:0.5 ratio, with a small amount of fertilizer such as soybean cake and bone meal added. In spring, from March to April, take out the tubers, remove the rotten parts, select stem pieces with 2-3 healthy buds and bury them in the potting soil, preferably with the bud tips exposed above the soil. Because canna lilies greatly love fertilizer and tolerate moisture, the pot should be watered thoroughly. When the 5th leaf has grown, apply a fully rotted topdressing once every 7-10 days, and water after fertilizing. Generally, apply a 1% ferrous sulfate fertilizer solution once a month, or add a small amount of plant ash, to encourage the stems to grow straight and robust, the leaves to be green and thick, and the flowers to be brightly colored. Stop fertilizing during the flowering stage. If the plant is placed in a relatively cool spot while flowering, the flowering period can be extended. When the flowers at the stem tips fade, the stems and branches should be cut off from the base at any time so as to encourage new shoots to sprout.
When potting canna lilies, greenhouse germination treatment can be used to make them bloom earlier. To do this, in February to March, cover the old roots shallowly with moist sand or loose peat soil, just enough to cover the rhizomes, and place them at 16°C to germinate. After the buds on the rhizomes sprout, cut the old stems into several pieces, each with more than 1 bud, and plant them separately in flower pots with a diameter of 10-12 cm. In April, repot them once more, using pots with a diameter of 15-20 cm depending on the actual situation. In mid-May, move them outdoors for care or take them out of the pots and plant them in the open ground, and they will bloom in July to August.
Potted canna lilies sometimes develop scorched and yellowing leaf edges, mainly caused by applying too much ferrous sulfate, or by drought and exposure to scorching sun. In the hot summer, watering with water that is too cold can also cause leaf edges to scorch, and if fertilizer is applied too strongly during the height of summer, it can even burn the rhizomes and “burn them to death”. Therefore, when the temperature reaches above 40°C, the canna lily can be moved to a ventilated, cool place. Around Frost's Descent, the potted canna lily can be moved to a place at 5-10°C, where it can safely overwinter; during overwintering, stop fertilizing.
For potted canna lilies, from May to August each year, watch out for leaf-roller pests so that they do not damage the tender leaves and flower spikes. They can be controlled by spraying 50% dichlorvos at 800 times dilution or 50% chlorbenzuron emulsifiable concentrate at 1000 times dilution. Canna lilies planted in the ground occasionally suffer from cutworm infestation; they can be caught by hand, or the soil around the roots can be drenched with trichlorfon at 600-800 times dilution for control.