How to Grow Fennel Seeds? Detailed Guide to Planting Methods and Precautions

The stems and tender leaves of fennel can be used as a vegetable, while the seasoning fennel is the dried mature fruit of the fennel plant. So, how do you grow fennel seeds?

1. Sowing methods

①Direct sowing has two methods: winter sowing (baodan) and spring sowing. For winter sowing, before the previous winter, sow the seeds into frozen farmland that has been pressed with salt and has suitable moisture (in the Kashgar reclamation area, November 25 to December 5, or using a 3 cm soil temperature below 5°C as the indicator), and harvest in the second year. Spring sowing is sowing, managing, and harvesting in that spring (the degree to which the spring sowing time is advanced has a non-linear positive correlation with fennel yield).

②Intercropping makes use of fennel's short growth period. After sowing the wide-and-narrow-row crops under plastic film in spring, intercrop fennel in the wide rows. For intercropping, it is best to do so before April 12 or when the 5 cm soil temperature is no higher than 15°C.

2. Variety selection

It is advisable to choose Shache small fennel with strong branching ability, high yield, lodging resistance, and plump seeds that have undergone purification and rejuvenation and screening.

3. Sowing requirements

Direct-sown fennel has two methods: hole sowing and drilling. Winter sowing is mainly hole sowing (row spacing 20-30 cm, hole spacing 9-12 cm), while spring sowing is mainly drilling (30 cm equal row spacing, plant spacing 5-8 cm). Intercropping uses hole sowing. Sowing depth is 1.5-2.5 cm, and the soil is pressed down after sowing. The seeding rate is 22.5-30 kg per hectare (1,000-grain weight 1.3-1.8 g). For hole sowing, 300,000-500,000 holes per hectare, retaining 1.4-2 million seedlings; for drilling, retaining 1.5-1.8 million seedlings.

4. Management

①Field management in early spring centers on increasing temperature and preserving soil moisture. For direct-sown fennel, shallow harrowing and pressing should be carried out before emergence. If it rains before emergence, harrow the field promptly to break up crusting, so as to preserve soil moisture and promote early emergence and early growth. The direction of shallow harrowing should be perpendicular to the sowing direction, with a harrowing depth of no more than 2 cm, and with a clod-crushing press attached.

②Field management at the seedling stage focuses mainly on chemical regulation, supplemented by manual weeding and thinning/final singling. At the 2-4 leaf stage of fennel seedlings, spray foliar fertilizer once (1%-2% monopotassium phosphate + 0.5%-1% urea). At the 5-8 leaf stage, spot-spray 0.15%-0.3% mepiquat chloride on overly vigorous field plots to increase the thickness of the basal internodes of vigorous seedlings, reduce plant height, and prevent later lodging.

③Field management during the flowering and fruiting stage focuses on preventing waterlogging damage from accumulated rain, nourishing roots and preserving leaves, promoting seed filling, and increasing grain weight. Small fennel is relatively drought-tolerant but not waterlogging-tolerant. If rainfall occurs in May-June and field water accumulation exceeds 8 hours, waterlogging damage will occur, causing plant death or even total crop failure. Therefore, when moderate to heavy rain occurs, drain the field promptly.

Although fennel has low water and fertilizer requirements during the flowering and fruiting stage, this stage overlaps for a relatively long time. Abnormal climate and soil drought can adversely affect flowering, fertilization, and yield. Foliar spraying of boron and zinc micronutrient fertilizers at a concentration of 0.2%-0.4% can increase the seed-setting rate. In the middle and late stages of fennel growth, for patchy spots showing fertilizer deficiency and premature aging (yellowing leaves), spray 1.5%-3% urea foliar fertilizer to improve the plant's ability to absorb nutrients through roots and leaves and promote normal fruit ripening. For patchy spots with dark green leaves and a tendency toward delayed maturity, spray 0.2%-0.4% monopotassium phosphate to increase the 1,000-grain weight and achieve a consistent overall harvest period.