According to almanac tradition, cover crops belong to the leaf group. The almanac rule plants that group in the first quarter of the Moon (new moon to first quarter), on days when the Moon is in a fruitful or semi-fruitful sign. The next Traditional days run October 10-13, 2026 (Moon in Libra/Scorpio) and October 16-18, 2026 (Moon in Capricorn). No effect of the Moon on crops has been proven, and your state’s calendar comes first.
What the tradition says about planting cover crops
Gardeners who plant by the Moon sort crops into three types, and each type gets a quarter of the lunar cycle. This convention files cover crops under the leaf type, which covers leafy crops and crops whose seed is outside the fruit. The almanac rule is to sow that type between the new moon and the first quarter. If you are new to the idea, our overview of planting by the moon explains where it comes from.
| Crop type | Almanac quarter | Examples in the almanac lists |
|---|---|---|
| Leaf (cover crops are filed here) | First quarter: new moon to first quarter | Lettuce, spinach, cabbage, broccoli, celery |
| Fruit | Second quarter: first quarter to full moon | Tomatoes, peppers, beans, squash, corn |
| Root | Third quarter: full moon to last quarter | Potatoes, carrots, garlic, onions, beets |
The fourth quarter, from last quarter to new moon, is the almanac’s rest period. Tradition reserves it for weeding, pruning, turning the soil and composting rather than sowing.
Many almanacs then add a second filter, the Moon’s sign. This convention labels Cancer, Scorpio and Pisces fruitful. It labels Taurus, Libra and Capricorn semi-fruitful. Aries, Gemini, Leo, Virgo, Sagittarius and Aquarius are labeled barren, although sources differ on Virgo, Sagittarius and Aquarius. The Traditional days on this page combine the quarter rule with a fruitful or semi-fruitful sign.
Now the plain part. No effect of the Moon’s phase or sign on germination or yield has been established. The numbers point the same way. The Moon’s tidal pull at the Earth’s surface is about 1.1 millionths of a meter per second squared, roughly one ten-millionth of gravity (1.1 x 10-7 g) at its strongest. That figure is calculated from the constants in the NASA Moon Fact Sheet, including the 29.53-day phase cycle and the 384,400 km mean distance. It is far too small to move anything as small as a seed or a root. Treat this page as a guide to an old custom, not as a forecast of results.
Traditional cover crops planting days, 2026 and 2027
Every window below applies the almanac quarter rule plus a fruitful or semi-fruitful Moon sign. Days are read at noon Eastern time (ET), so a gardener on Pacific time sits three hours behind these clocks. If you want the sign for each day of the current month, the October 2026 moon calendar lists it.
| Month | Traditional days | Moon sign |
|---|---|---|
| October 2026 | October 10-13 | Libra/Scorpio |
| October 2026 | October 16-18 | Capricorn |
| August 2027 | August 6-8 | Libra/Scorpio |
| September 2027 | September 2-5 | Libra/Scorpio |
| September 2027 | September 30 | Libra |
| October 2027 | October 1-3 | Libra/Scorpio |
| October 2027 | October 6 | Capricorn |
| October 2027 | October 29-30 | Scorpio |
The months shown are those when gardeners in much of the country plant cover crops. Your state may start earlier or later, so only the rows that fall inside your own state’s window count. A row outside that window is simply not available to you, whatever the almanac says.
Because the Moon changes sign during the day, treat the first and last day of each run as soft edges. A run listed as Libra/Scorpio, for example, includes a change of sign somewhere inside it. If you plan to plant on the first or last day, check the hour of the sign change in a day-by-day calendar before you commit.
Check your state first: when to plant cover crops where you live
The order of decisions matters. Start with your state’s planting calendar for cover crops, since that sets the weeks when seed can go in the ground at all. Only after that does the Moon come in, if you want it. Our page on when to plant cover crops where you live carries the dates, and the state guides cover the local detail. This page deliberately gives no planting date, soil temperature or frost date. Those belong to the pages built to hold them.
The Moon never overrides the calendar of your place. Frost dates and soil temperature decide whether cover crops can go in the ground. The Moon, if you follow it, only chooses among days your state’s calendar already allows.
In practice that gives you three short steps:
- Find your state’s planting window for cover crops and note its first and last day.
- Lay the traditional days from the table above over that window.
- Pick a traditional day that falls inside it. If none does, plant by the state calendar and leave the Moon out this season.
That last case is common enough in a short window and nothing to worry about. The almanac is a custom layered on top of local conditions, never a replacement for them. A season with no overlap is just a season you plant by the state guide alone.
A fair way to try it
If you are curious whether the tradition shows anything on your own ground, a simple split test is the only fair way to find out. Here is how to set it up:
- Choose one area and divide it into two matched halves, with the same soil, sun exposure, seed and seeding rate.
- Sow the first half on a traditional day from the table, one that also sits inside your state’s planting window.
- Sow the second half on an ordinary day in the same week, a day that is not in the table. Water and handle both halves the same way.
- Label both halves clearly so you do not lose track by midseason.
- Write down the date each half emerges, and note how the two compare when you cut or turn them under.
Be honest about what this can show. A single season will not settle anything. Weather shifts from week to week, soil varies across a bed, and one pair of halves is a very small sample. Several seasons of notes mean more than one.
Still, this is the only way a home gardener can judge the custom for their own plot. Reading about it won’t do it, and neither will trusting someone else’s garden. Your notes, from your soil, are the evidence that counts for you.
Questions about planting cover crops by the moon
Does the tradition say to plant cover crops in a waxing or a waning moon?
According to almanac tradition, a waxing moon, and specifically the first quarter between new moon and first quarter. The second quarter is also waxing, but the convention gives it to fruit crops such as tomatoes and beans. The waning quarters go to root crops (third quarter) and to rest tasks (fourth quarter). More on the waxing half is in our page on planting in a waxing moon.
What if the traditional day falls on a frost?
The tradition has nothing to say about weather, because the almanac rule only names days by the Moon. Your state calendar decides whether planting is possible that day. If the traditional day does not suit local conditions, skip it and look at the next window in the table, or plant on an ordinary day your state calendar allows.
Do I need to follow the Moon sign as well?
Not if you only want the quarter rule. Many almanacs add the sign as a second filter, and the windows in the table already apply both. The biodynamic system of Maria Thun sorts days differently: its leaf days are Cancer, Scorpio and Pisces, its root days are Taurus, Virgo and Capricorn, and its flower days are Gemini, Libra and Aquarius. A gardener who follows that system would keep only the Scorpio part of a Libra/Scorpio run. They would also set aside the Capricorn runs, which that system calls root days. Neither approach is proven, so choose the one you are willing to keep notes on.