Planting by the Moon

How the Moon's phase decides what to plant

The first half of the rule follows the phase. From new moon to full moon the Moon is waxing, and that stretch suits sowing and transplanting crops that bear above ground, such as leafy greens, tomatoes or annual flowers. Waxing and waning each last about two weeks, so the window turns over twice a month.

From full moon to new moon the Moon is waning. Waning days are for root crops like potatoes and carrots, plus bulbs, perennials and trees. The Old Farmer's Almanac, which has printed the phase rule since 1792, gives the traditional reasoning: as moonlight increases, plants put energy into leaves and stems, and as it decreases, into roots.

Fruitful and barren signs

The phase tells you what to plant. The sign tells you whether to plant at all. The Moon passes through all twelve signs in about 27 days, staying roughly two and a half days in each, so good and poor stretches alternate every few days.

Fruitful signs make the best planting days: Cancer, Scorpio, Pisces. Semi-fruitful signs are good: Taurus, Capricorn, Libra. Flowers do well with the Moon in Libra. Barren signs are Aries, Gemini, Leo, Virgo, Sagittarius, Aquarius. William Lilly's Christian Astrology (1647) named Cancer, Scorpio and Pisces as fruitful and Gemini, Leo and Virgo as barren. Later almanacs added Aries, Sagittarius and Aquarius to the barren side and called the other three semi-fruitful. On a barren day, do not plant. Weed, till, clear beds, harvest or deal with pests instead.

How to use the 60-day table

Start with frost dates, your hardiness zone and soil temperature. The Farmers' Almanac says the same, and suggests asking a local extension office. Those set the season. The Moon only helps you choose days inside that window, and it should never be a reason to miss it.

Once you know what is safe to put out, scan the table for a day whose phase matches the crop and whose sign is fruitful, or semi-fruitful if nothing better is close. If the right phase falls on a barren day, wait for the next good one or use the day for chores.

Phase and sign are read at noon Eastern time. On a day when the Moon changes sign, the table shows the time it does. Readers in other US time zones can see a sign change land on the neighboring day, so check the edges.

Does planting by the Moon work?

It is a long tradition, not a proven method. The Old Farmer's Almanac repeats the claim that the Moon draws soil moisture upward the way it pulls the tides, and it admits the evidence is mixed: some studies find a small effect, others call it folklore. The Farmers' Almanac, in print since 1818, goes further and combines phase with sign in one calendar. Seeds sown on a wrong day still grow when soil, water and light are right. Gardeners who follow the Moon mostly use it as a rhythm for sowing, plus chores such as weeding and harvesting.