In the first ten days of May every year, the skin of the fruit of Sagittaria wilfordii begins to turn red or even purple black, and a large number of fruits begin to fall off. This is the best time to collect seeds. Generally, the age of poisonous arrow tree that can bear fruit is about 100 years, and its trunk will be very tall. If you want to climb to the tree to collect fruit, it will be difficult, so you need to wait until the fruit falls naturally to collect. For the collected fruit, it must be cleaned, and then the peel must be removed to get an egg shaped poison arrow seed inside. Next, put them into the water, take out the full seeds to dry, and wait for the next sowing.
According to the germination characteristics of Sagittaria seeds, if you want to improve the germination rate, it is generally recommended to sow in time after picking, you can use on-demand or trenching. The spacing between the seeds is 3cm × 10cm. Generally, 250 seeds are sown in a square soil. After the seeds are sown, 2cm soil layer shall be covered, and then straw shall be covered. Attention shall be paid to watering to keep the soil moist. Under normal circumstances, 25 to 30 days, the seeds will start to germinate, 40 days to the peak of seed germination, 55 days when the seeds are generally all germinated.
One month after the small surface is drilled out of the land, some low concentration livestock manure or 0.1% compound water and fertilizer can be applied. When four or five leaves are grown, they can be transplanted into the nutrition bag for cultivation. The substrate in the nutrition bag is generally 20% burnt soil and 80% sandy soil. The transplantation time is in rainy days or in the afternoon. Pay attention to shading. One month after transplanting, we can apply fertilizer. The concentration needs to be thin first and then thick. In August and September, we can add some potassium fertilizer, which is conducive to the safety of seedlings in winter.
In general, the two-year-old nutrition bag seedlings should be selected for planting. One month before planting, the seedlings should be divided and picked up first, and then planted after the seedlings grow stably. When planting, we need to pay attention not to hurt the root of the poisonous arrow tree, but also to cover the shade. The soil must get rid of weeds to make sure that the soil is loose and moist, but it can't accumulate water, and poisonous arrow wood can't be flooded.
