How to Grow Geraniums? A Detailed Guide to the Latest Cultivation Methods
Geranium (Pelargonium) is a perennial herbaceous plant of the genus Pelargonium in the family Geraniaceae, native to southern Africa and widely cultivated around the world. It is highly adaptable, with bright flower colors and a long flowering period. It is suitable for indoor display, flower bed arrangement, and more. In the West, it is an excellent flower for decorating windowsills, and on the European continent, such as in Germany and Austria, it is especially common. Let us take a look together at how to grow geraniums!
Propagation Methods for Geraniums
1. Seed propagation: This can be done in both spring and autumn, with indoor pot sowing in spring being preferable. The optimal germination temperature is 20-25°C. Geranium seeds are not large, so after sowing, the soil covering should not be too deep; germination occurs in about 2-5 days. If sown in autumn, the plants can bloom in the summer of the following year. Seedlings grown from seed propagation can be selected to produce excellent intermediate-type varieties.
2. Cutting propagation: Cuttings can be taken at any time except from June to July when the plant is in a semi-dormant state, but spring and autumn are best. In summer, high temperatures make cuttings prone to blackening and rotting. Select cuttings 10 cm long, with the top portion being best, as it has vigorous growth and roots quickly. After cutting, let the cut surface dry for several days to form a film before inserting into a sand bed or a mixed substrate of expanded perlite and peat. Be careful not to damage the stem bark of the cutting, otherwise the wound will easily rot. After insertion, place in a semi-shaded area and maintain a room temperature of 13-18°C. After 14-21 days, roots will form, and when the roots are 3-4 cm long, they can be potted.
3. Tissue culture: Geraniums can also be propagated by tissue culture. Using MS medium as the basic medium, add 0.001% indoleacetic acid and kinetin to promote callus and adventitious bud formation from explants, and use 0.01% indoleacetic acid to promote rooting. The tissue culture method provides a new approach for the breeding of improved varieties and the selection of new cultivars of geraniums.
Cultivation Methods for Geraniums
1. Temperature control: The most suitable temperature for geraniums is 10-20°C, which means spring and autumn are the most suitable seasons; winter is too cold and summer is too hot. Therefore, in summer, be sure to prevent exposure to direct sunlight and place it in a shady spot. In winter, the indoor temperature should not be lower than 0°C, otherwise it will suffer frost damage. If there is no heating equipment, turning on a 200° large light bulb in a small room also has a certain anti-freeze effect.
2. Water control: Geraniums should not be overwatered. If you find the roots of the geranium rotting, it may be due to excessive watering combined with relatively muggy weather. Control the watering frequency to once every two or three days, and each time water generously to ensure thorough watering.
3. Soil selection: Geraniums are suited to sandy soil. Mixing some sand into the soil bought at the flower market is more beneficial for the growth of geraniums.
4. Weather effects: Strong winds will break geraniums, and heavy rain will cause the root system of geraniums to be soaked by rainwater, resulting in oxygen deprivation in the roots and subsequent rotting.
6. Fertilization control: Applying too much fertilizer at once will cause dehydration of the geranium. If too much fertilizer is applied, for example, too much nitrogen fertilizer, the plant will grow excessively and not bloom. After over-fertilizing, watering more frequently can alleviate the symptoms.
7. Light conditions: Sufficient sunlight helps geraniums bloom, but when the temperature is too high, direct sunlight is not suitable. In spring and autumn, expose them to more sunlight; in summer, pay attention to the temperature, and if it is too high, avoid exposing geraniums to light.
Precautions for Geraniums
January: Place in a sunny spot to prevent damage. When the weather is clear, water, preferably at noon; avoid using snow water or cold water.
February: Apply a dilute liquid fertilizer once every 2 weeks, appropriately increase the amount of watering, and pay attention to ventilation on nice days.
March: Cutting propagation can be combined with pruning. For cuttings, select vigorous one-year-old branches from mother plants that bloom frequently, are of pure variety, and have good growth. Each cutting should be 4-6 cm long with 2-3 nodes; remove the lowest leaf and place in a cool place for a day. After the cut surface dries, insert. Choose sandy land with high, dry terrain and good drainage, deep plow and rake level to make a seedbed, then mix 60% yellow mud with 40% rice husk ash and spread it on the seedbed for cutting use.
April: Continue cutting propagation. For seed propagation, since the seeds are not large, do not cover with too much soil; after sowing, keep warm at 20-25°C, and germination can occur about 2 weeks after sowing. After cuttings have rooted, they should be potted in time. Use a mixture of 1 part each of humus soil, rice husk ash, and garden soil, plus some bone meal, phosphorus, potassium, and other compound fertilizers. April to June is the peak flowering period; apply a dilute liquid fertilizer once a week. In late April, they can be moved outdoors for cultivation. When seedlings are 12-15 cm tall, pinch the tips to promote side branches.
May: After flowers fade, promptly cut off the faded flowers. When cutting, it is best to cut 3-4 cm from the first leaf below the flower stalk, to help reduce nutrient consumption and promote new flower growth. Do well in fertilizing, watering, and pest and disease control. Seeds mature 40-50 days after flowering and should be harvested promptly, dried, and stored.
June: As the flowering period ends, short pruning should be carried out to make the plant short, sturdy, full, and attractive. Do not water or fertilize for one week after pruning, so that the cut surfaces shrink and dry, avoiding rot from moisture. By late June, the plant enters a semi-dormant state; it should be placed in a cool, shaded area, watering should be controlled, and fertilization stopped.
July: Water mainly in the early morning each day, supplemented in the evening, watering when dry. After rain, drain promptly; never allow water to accumulate in the pot.
August: Autumn cutting propagation can be carried out. Geraniums grow rapidly and need repotting every year, replacing with new soil, and heavy pruning, leaving about 10 cm at the base. Also appropriately trim some longer fibrous roots, and appropriately remove excess shoots from the upper part.
September: Continue cutting. They grow rapidly; apply a dilute liquid fertilizer about once every 10 days, and do not splash it onto the leaves when fertilizing.
October: Flowering begins and continues until June of the following year. Pay attention to placing in a wind-sheltered, sunny spot to prevent cold air invasion. In late October, move into the greenhouse and pay attention to ventilation.
November: Ensure sufficient sunlight, control watering, fertilize in time, strengthen ventilation, and prevent the occurrence of pests and diseases.
December: The room temperature must not be lower than 5°C. Do not water unless dry, and promptly remove faded flowers and dead leaves.