It's the right time to raise autumn vegetable seedlings, and growing strong seedlings is key
Recently, temperatures have continued to rise, with abundant sunshine, increased rainfall, and hot, humid weather. In greenhouses and polytunnels, most fruit-type vegetables have entered the vine-pulling stage, while some heat-tolerant open-field varieties have entered the peak harvest period. This period is also the key time for raising seedlings of autumn open-field cauliflower, cabbage, and autumn polytunnel tomatoes, peppers, and eggplants, as well as the suitable sowing time for carrots, early-maturing Chinese cabbage, and open-field cucumbers. At present, it is necessary to do a good job of harvesting, seedling raising, and sowing under the high heat of summer, to ensure increased yield and income for the whole year.
A. Autumn open-field crops such as cauliflower, cabbage, kohlrabi, and lettuce
Choose to raise seedlings from late July to early August. For open-field cucumbers, select heat-tolerant, early-maturing, disease-resistant varieties, sow in early to mid-July, and supply the autumn off-season market from late August to early October. Apply sufficient organic fertilizer, make high ridges shaped like tile ridges, do not lay plastic film, and plant at a density of 70-75 cm x 30-33 cm.
B. Peppers, sweet peppers, and colored bell peppers grown in autumn solar greenhouses
Raise seedlings in late July; greenhouses with poor insulation performance should raise seedlings 5-10 days earlier, and colored bell peppers should be raised appropriately earlier, with the suitable sowing time in mid-July; the general seedling age is 45-50 days, transplant in late August to early September, and harvest and market from early November to the Spring Festival period. For raising seedlings in polytunnels with good ventilation and relatively low temperatures, use 50-cell plastic plug trays, with special seedling substrate or peat, vermiculite, and perlite as the substrate. Do a good job of hot-water seed soaking and soaking to promote germination, germinate for 6-7 days at 25°C-30°C, and sow when the seeds begin to sprout.
C. Autumn-winter crop greenhouse tomatoes
Generally raise seedlings in mid-to-late July, transplant in mid-to-late August, and harvest from mid-November to mid-January; greenhouses with poor insulation performance should raise seedlings appropriately earlier. In recent years, tomato yellow leaf curl virus disease has occurred severely. Once infected, it often causes large yield reductions, or even total crop failure. The best preventive method is to start from the seedling stage, using shade nets, greenhouse film to protect against rain, and insect-proof nets to protect against insects and other "full protection" measures to cultivate strong seedlings, and strictly prevent whiteflies from transmitting the virus.
D. Autumn polytunnel cucumbers
Transplant in late July; for cucumbers, select early-maturing, disease-resistant, good-quality varieties such as "Zhongnong 16", raise seedlings in mid-July, transplant in early August, use 72-cell plastic plug trays for seedling raising, with peat, vermiculite, and perlite as the substrate; cucumbers can also be sown directly in late July.
E. Autumn polytunnel celery
Transplant in early to mid-September. The seeds must be germinated at low temperature before sowing. After soaking the seeds for 24 hours, rub them with your hands to remove the germination-inhibiting substances on the seed coat, then place them at 17°C-20°C to germinate for 6-7 days; they can be placed 50 cm above the water surface of a machine well to germinate. Sow when the seeds have just begun to sprout, and do a good job of shading and rain protection for the seedling-raising tunnel.
F. Early-maturing Chinese cabbage
Select early-maturing, heat-tolerant varieties such as "Xiaoza 56" and "Beidi", and harvest and market around National Day and the Mid-Autumn Festival. Apply sufficient base fertilizer, prepare the land carefully, water between rows after sowing to lower the temperature, and prevent virus diseases, aphids, cabbage caterpillars, and other pests and diseases from the seedling stage onward.
G. Autumn open-field carrots
Begin sowing in mid-to-late July, and select high-quality, high-yield varieties such as "Hongxin 228" with a well-shaped, attractive root form and the "three reds" of skin, flesh, and core. Apply 4000 kg of fully decomposed, finely broken high-quality organic fertilizer or 3000 kg of commercial organic fertilizer per mu, and after careful ploughing and leveling, make high ridges for sowing, spreading the seeds evenly, using about 300 g of seed per mu. (Gan Min)