Before their flowering and fructification is the best time to remove spiny sowthistle; otherwise, it can be very difficult to control them. After they have flowered and fructified, their seeds can spread very quickly, hence, the weeds should be removed more often, and precautions should be taken in advance the following year. Before their flowering and fructification is the best time to remove spiny sowthistle; otherwise, it can be very difficult to control them. After they have flowered and fructified, their seeds can spread very quickly, hence, the weeds should be removed more often, and precautions should be taken in advance the following year. You can effectively inhibit seed germination and seedling growth by covering the soil with sawdust, straw, or black mulches. Even if spiny sowthistle has flowered and fructified, this method can also prevent more seeds from germinating in the soil. Pull out spiny sowthistle before its fructification being sure to wear gloves or use tools. If the soil is too dry, you can soften it by watering it thoroughly; this can help remove the root systems. After, employ deep tillage to remove any weed roots left in the ground. This is especially effective for weeds that are low-growing or are in the seedling stage. If you mow spiny sowthistle before its fructification, you can control their spread. Frequent mowing inhibits their growth and fructification, so, within a year, they'll be gone. Plowing the land in fall or early spring can control its growth. Before planting, you must plough and pull out all roots of perennial weeds. Discard the roots, expose them to the sun for a long time, or bury deep. Another option is to make organic fertilizer with the roots or compost the weeds. Whenever you remove weeds, especially if they are toxic, thorny, or have allergenic sap, wear gloves and avoid direct contact. If they're in bloom, add special masks to prevent triggering a pollen allergy.