How to Plant Calendula Seeds? Detailed Planting Methods and Steps

Calendula is one of the most common herbaceous flowers in early spring gardens and cities, with yellow or orange-yellow flowers, and it is also very easy to grow. So how do you plant calendula seeds?

1. Land preparation

The farmland for planting calendula should be chosen with deep, loose soil that drains and aerates well, and the previous crop is best as cucurbits, corn, or legumes. When the temperature begins to rise and the plow layer thaws, use a heavy harrow with a leveling board as soon as possible. Harrow to a depth of 20-25 cm so that the surface soil is finely broken up, then level and press it flat so the field surface is even. While harrowing, apply a base fertilizer according to soil fertility, with 10-15 Kg of nitrogen fertilizer and 5-10 Kg of phosphorus fertilizer per mu, and also apply plenty of organic fertilizer.

2. Seed treatment

First select excellent calendula hybrid seeds. Before sowing, sun the seeds on a clear, windless day by spreading them on a tent or concrete surface. The thickness should be about 1 cm, sun them for 4-6 hours, and turn them once every 1 hour. Through exposure to ultraviolet rays, pathogens on the seed surface are killed, seed vigor is enhanced, and the germination rate is increased.

After the land is covered with plastic film, the soil temperature rises quickly. Choose the sowing period after complete frost has ended, when the average temperature is steadily above 13°C and the surface soil temperature is above 10°C, and sow in time. Use a sowing punch with a diameter of 3-5 cm to make holes 35 cm from the center line of the film, with a hole spacing of 30 cm and a hole depth of 7-8 cm. The hole positions on both sides of the ridge should be staggered in a triangle, and there must be no loose soil in the holes. Place 3 or 4 seeds per hole, and cover with fine moist sandy soil.

3. Field management

Generally, seedlings emerge 5-10 days after sowing. Because emergence time is closely related to sowing depth, soil type, and local temperature, sowing too deep, excessive soil moisture, or too low a temperature will delay emergence. When the seedlings are about 5 cm tall. When the weather is suitable, break the film and release the seedlings in time to avoid burning the seedlings.

When the seedlings have grown 2-3 true leaves and are about 20 cm tall, thin them, leaving 2 strong seedlings per hole; at 3 pairs of true leaves, final thinning should be done, leaving 1 healthy, disease-free seedling per hole; at the same time, remove weak, small, and diseased seedlings, and transplant seedlings to fill gaps where seedlings are missing. The principle for retained seedling density is “sparse on fertile land, dense on poor land.” When the seedlings are about 30 cm tall, combine weeding with cultivation and loosening the soil, take soil from the furrows and bank it around the base so that adventitious roots form at the base, preventing lodging and breaking.

4. Water and fertilizer management

Calendula is a plant with moderate water needs. Lack of water will cause the plants to be short, while excessive irrigation will cause excessive vegetative growth, and both will reduce yield because the flower size decreases. Generally, according to the rainfall of that year, irrigate the first water in mid-June, the second water in late July, and the third water from late August to early September. The amount of irrigation depends on soil moisture, and border irrigation and drip irrigation are best. During the bud stage, irrigate in time together with fertilization to promote more flowering and larger flowers. For fields lacking fertilizer and fields in the fresh flower harvest period, foliar topdressing can be carried out. This promotes plant growth and increases late-stage fresh flower yield.

5. Pest and disease control

During the calendula growing period, spraying the leaves 2-3 times with potassium dihydrogen phosphate combined with microelement fertilizers can help increase nutrition and resist pests and diseases. Spraying 70% mancozeb 600-700 times solution before pests and diseases occur can provide protective effects. When diseases occur, spray for control with thiophanate-methyl, amobam, agricultural streptomycin, and the like.

The main insect pests of calendula are cutworms and red spider mites. To control cutworms, when preparing the land, combine base fertilizer application with applying isofenphos-methyl; use 0.5 Kg of 40% isofenphos-methyl per mu, mix with 30 Kg of water, and spray evenly on the ground surface. Or use 0.5 Kg of 40% isofenphos-methyl, mix with an appropriate amount of water and 100 Kg of sand, and broadcast evenly. Incorporate it into the soil while preparing the land with a harrow. To control red spider mites, spray 1.8% nongkemite emulsifiable concentrate 2000 times solution during the calendula growing period.