Younger parsley plants have the strongest flavor. The leaves can be harvested even after the first year, but if you have the option of harvesting leaves from a plant in its first year of growth, doing so will give you the best yield and product. Check the stems. If the stems have three or more clusters of leaves, they are mature enough to harvest from. Stems with one or two segments should be left alone. Most parsley plants will be ready to harvest from within 70 to 90 days after you initially plant them. When harvesting entire stems or bunches of parsley, snip the herb off at the base of the plant instead of cutting from the top. Cutting the parsley near the base of the plant will encourage the plant to produce even more stems, resulting in an overall bushier parsley plant with an improved yield. If you only plan on harvesting a few small sprigs of parsley for immediate use, you should snip them off from the outer portion of the plant and not from the inside.  Even if you plan on cutting a few full sprigs at the base of the plant, you should cut from the outside instead of the inside. The inner part of the plant will benefit from being able to mature longer. Removing leaves from the outside will ensure that the oldest growth is being harvested, thereby preventing it from browning or otherwise remaining on the plant too long. Harvesting old growth also allows the plant to focus its energy on producing and maturing the newer growth. This effort will produce an overall healthier parsley plant. Parsley will continue to grow throughout the entire season, even after you harvest the leaves. As such, you can have a steady supply of the herb and do not need to harvest it all at once. Parsley grown outdoors will usually remain a vibrant green until late fall to early winter. Once the color starts to fade, its flavor will decline dramatically. Until that happens, though, you can keep harvesting the plant on an ongoing basis without a loss to the herb's flavor or health. If your parsley is kept outdoors and unprotected,...

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Write a summary of the previous text in Vietnamese:
Chọn cây non để hái. Chờ cho đến khi cuống lá có đủ 3 đoạn. Cắt lá mùi tây tại gốc cây. Cắt lá mùi tây ở vòng ngoài. Thu hoạch liên tục. Hái nhiều rau vào cuối mùa. Phơi khô rau mùi tây để dễ dàng dùng dần.