The effect of bulb planting time and type of mulch on the yield of Allium aflatunense B. Fedtsch.

The aim of the study was to determine the effect of bulb planting time and the type of mulch on the morphological traits of plants and on bulb yield of Allium aflatunense B. Fedtsch. 'Purple Sensation'. Bulbs of 12 cm diameter were used as the study material. The bulbs were planted in plots on three dates: September 15th, October 1st, and October 15th. The plantation was mulched after frost with two types of mulch: composted pine bark and wheat straw. Phenological phases of the plants were observed during the growing season. At the full flowering stage, several observations and measurements were taken: length of leaves, length of inflorescence peduncle, peduncle diameter, inflorescence diameter, and number of flowers per inflorescence. After harvest, total numerical and weight yield of bulbs were evaluated as well as number and weight of the largest bulbs (21–22 cm diameter). The study showed that in order to obtain Allium aflatunense of high ornamental value, which is determined by the number of flowers per inflorescence and the inflorescence peduncle diameter, bulbs need to be planted in the middle of September. Bulb planting in October leads to production of inflorescences of greater diameter. The optimum method of Allium aflatunense cultivation which ensures production of good total yield of bulbs, expressed in its weight, is bulb planting on September 15th and soil mulching with composted pine bark or straw. Mulching a plantation of Allium aflatunense planted on September 15th with bark has a positive effect on the number and weight of bulbs of 21–22 cm diameter.