What does seven onions, eight garlic, nine oils and ten wheat mean?

Seven onions refer to the lunar calendar. You can plant onions in July.

Eight garlic means that you can go to kind of garlic in August of the lunar calendar.

Jiuyou is a kind of rape.

Ten wheat refers to planting wheat in October of the lunar calendar.

In the agricultural planting season, agricultural proverbs such as "plant cotton well before the long summer", "plant beans well after the Qingming Festival", "summer buckwheat with white dew", "seven onions, eight garlic and nine beans" and "nine oils and ten wheat" appeared. In agricultural production, we have accumulated "when ploughing is deep, loess turns into gold, crops grow well in half a year, and crops are rich in millet", "Three-point planting and seven-point management", "Crops are plowed three times without Mao Mao, wheat is hoed three times without claws", "One inch deep in winter is dung" and "Buckwheat needs no dung, as long as it stays in bed for three nights". After the 1990s, farmers realized the harm of widespread use of chemical pesticides to kill insects, and generally did not use pesticides to kill insects unless they had to. In the planting methods of early and late rice, we have accumulated new experience of "turning water into green, tillering in shallow water, expanding bracts in deep water, and strengthening seeds in dry and wet conditions". During the planting season, farmers abide by the motto that "early rice is more than May Day, and late rice is more than August Day".