Just like their big brothers who raise too much corn, wheat and cotton for their own good, peppermint farmers are raising too much peppermint for their own good.

But their own good is not necessarily the good of the rest of America, especially those who use peppermint-flavored candy, gum or toothpaste. So the peppermint farmers, mainly in Oregon, Washington and Idaho, are appealing for help from the secretary of agriculture, a corn and hog farmer named John R. Block.

Just as the Reagan administration is reiterating its determination to get the government out of farming, the peppermint growers are asking Block to give them a marketing order that would regulate the amount of peppermint oil that farmers and handlers could send to consumers.

The idea is to convert short green (the leaf) to long green (profits). Last year, the growers processed enough peppermint leaves to produce 3.5 million pounds of oil, which sold for $32 million. If Block approves the marketing order, about 600 farmers in 16 states would participate.

The Agriculture Department is giving the public until the end of the month to comment on the marketing order proposal, which, according to a USDA spokesman, fits within the guidelines for the orders that Block issued early last year.

But it remains to be seen how candy lovers at the Office of Management and Budget will view this. The OMB section that reviews marketing orders to see if they meet the guidelines is sitting on a USDA-approved renewal of a similar order for spearmint oil and saying nothing.

For months, the OMB and the USDA have been at each other's throats over marketing orders as a result of Vice President Bush's review of federal regulations that are unduly burdensome or costly.

The free-market Reagan administration was dragged into the marketing order flap early in 1981 when consumer advocates and some farmers protested the destruction of thousands of tons of California navel oranges, which could not be sold because of market-order quota restrictions.

As the flap waxed and waned, Carl A. Pescosolido Jr., a navel-orange grower in Exeter, Calif., bombarded administration officials, from Block on down, with letters and telegrams objecting to the restrictions that the marketing orders put on him. The officials were hard-pressed to ignore his calls to ideological purity.

Marketing orders were created in the early 1930s, when agriculture was in chaos and farmers sought federal authorization to assure their income by tailoring supplies of their products to expected demand.

The farm chaos of the 1930s is gone, but marketing orders march right on. There are now 48 of them in effect, regulating the flow and production of many fruits, vegetables and specialty crops. Supporters say they protect both consumers and growers; critics say they impede free enterprise and lead to price rigging.

That philosophical split has left the OMB generally on the side of the critics, and the USDA generally on the side of the supporters of marketing orders. Block carried out a study of the orders in 1981 and then set down guidelines designed to assure that the orders did not interfere with productivity and commerce.

"It is OMB's view that these orders restrict the entry of firms into the market," said an OMB official. "At certain points, they may be needed. But there should be a rebuttable presumption--that is, the burden of proof ought to be on the people who think these things are necessary."

"According to the guidelines, Block is supposed to live by the principles he set out," he said. "But it's still a tug-of-war between us and the USDA. They'll continue to send these individual orders over and we'll review them. We'll win some and we'll lose some."

The OMB won one last year when it rejected a tart-cherry set-aside order sought by producers in Michigan. But the USDA didn't back off. It has gone ahead with the spearmint and peppermint oil proposals and is considering a pecan research and promotion order.

Meanwhile, California kiwi growers, Georgia onion producers and the ginger-root people in Hawaii have made it known that they may come along at any time with proposals for marketing orders.

"I don't know what to tell you," a USDA marketing official said recently. "You hear about these airline pilots and dentists who've invested in kiwi plantings and now they're overproducing. A kiwi was 69 cents last year and now they're four for $1 at my Safeway--and I love kiwis. I don't know what a marketing order would do to that."