Farmers Almanac
The Farmers Almanac
Order your copy today!

Rare Full Flower Blue Moon Set To Rise On May 18th

Rare Full Flower Blue Moon Set To Rise On May 18th

On Saturday, May 18, 2019, at 5:11 p.m. Eastern Time, May’s Flower Moon officially turns full. This particular full Moon is also referred to as a “Blue Moon,” however some may be confused by this name. Most people know that we usually refer to a “Blue Moon” when we have two full Moons in a month (which happens on average every 2 1/2 to 3 years – read more here).  There is, however, an alternate definition for a Blue Moon, which is what the Moon on May 18th is.

The Seasonal Blue Moon Definition

Typically, each of the four seasons contains three full Moons. However, sometimes a particular season will have four. When that happens, the third full Moon of that seasonal lunar quartet is designated as a Blue Moon (although no one is sure why the third, and not the fourth, is the one that gets the Blue Moon moniker).

In 2019, spring in the Northern Hemisphere runs from March 20th to June 21st. During that time span of slightly more than three months, these are the full Moon occurrences (in Eastern Time zones):

  1. Full Worm Moon: March 20, 2019
  2. Full Pink Moon: April 19, 2019
  3. Full Flower Moon: May 18, 2019 (Blue Moon)
  4. Full Strawberry Moon: June 17, 2019

That final full Moon falls before the summer solstice, so it’s not the first full Moon of summer, but rather the fourth full Moon of spring. That makes the May 18th Moon—the third of the four full Moons of spring—a “Blue Moon.” It will also be the last seasonal Blue Moon until August 22, 2021.

And no, it will not be blue in color!

Check out all the dates and times of the full Moons here.


Previous / Next Posts


1 JoAnne { 06.10.16 at 5:29 am }

As a child growing up in the 40’s and 50’s, I remember my grandparents having a copy of the Farmers’ Almanac on their breakfast table; there was much conversation about gardening – when to plant. I learned much from them and was real happy when I found your website.

2 Wendi { 05.18.16 at 8:32 pm }

I had no idea…….it was just a much used saying. Now, when I say it, I will have an idea of why I am saying it and think about it… I am learning so much at this site……Thank you FA!

3 Bonnie Carniello { 05.18.16 at 3:59 pm }

Love the Almanac and this website! I love learning new things about the moon and the planets and what the Indians said about these things.

4 Sandi Duncan { 05.18.16 at 2:41 pm }

Both are true. If you check out this story there’s more to it, but a second full moon in a month is the popular definition of a “blue” moon, but it can also be a third in a season. To confuse matters even more, some call this full moon a full flower moon.

What is a Blue Moon?
May Flower Lore: Lily of the Valley

5 Lynnette Honiker { 05.18.16 at 1:56 pm }

8/24/09 FA article “What’s a blue moon?” states that this above information was made in error by some guy in the 1800’s who wrote for the Maine Farmers Almanac (another publication). So, which is it, true or not?

6 Wayne Keith { 05.18.16 at 1:36 pm }

Wikipedia states, “A blue moon is an additional full moon that appears in a subdivision of a year” The third is not additional, it is normal. The second in a month fits the definition perfectly, and is not as ambiguous as the third in a season.

7 Sandi Duncan { 05.18.16 at 2:41 pm }

Ha – enjoy!!

8 LarryB { 05.18.16 at 12:16 pm }

My wife gets this site at her office. Another “Blue” moon??? Looks like I’m taking her out to dinner….as she claims I only do so “once in a blue moon”. Damn you FA!! Haha.

9 Kevin Mahoney { 05.18.16 at 11:33 am }

So does this mean we’ll observe a Blue Honey moon?

10 Paul Smith { 05.18.16 at 11:04 am }

Thanks for educating us to something new to me. Am I missing how often this blue moon alternative occurs?

11 Dwight { 05.18.16 at 10:54 am }

Why is the third full moon called the Blue Moon? The fourth full moon is the rarer occurrence.

12 Pat Blake { 05.18.16 at 9:56 am }

Love reading your articles. Always learn something new and interesting!

13 Marcy { 05.18.16 at 9:02 am }

I wonder why it’s called “blue”. Still this is fascinating information. As an educator Farmers Almanac is a great resource.

14 Jersey Dealer { 05.18.16 at 8:40 am }

Great information about the 3rd spring moon. Very informative, keep up the great articles.

15 Sandi Duncan { 05.18.16 at 2:43 pm }

If you read this article, there is one belief that says “Why “Blue” Moon? For the longest time nobody knew exactly why the second FULL MOON of a calendar month was designated as a Blue Moon. One explanation connects it with the word “belewe” from the Old English, meaning, “to betray.” Perhaps, then, the Moon was “belewe” because it betrayed the usual perception of one FULL MOON per month.”

What is a Blue Moon?

16 Nancy Carver { 05.18.16 at 7:41 am }

Why blue? What has the color blue got to do with any of this?

17 Suzie Medendorp { 05.18.16 at 7:38 am }

I have learned so much from your articles. Always wondered about the blue moon lore.
Thank you for sharing !

18 Sandi Duncan { 05.18.16 at 2:44 pm }

Thanks Ellen!!

19 Ellen Campbell { 05.18.16 at 7:16 am }

The explanation of this second kind of blue moon is very interesting. I’m going to refer my Facebook friends to Farmers Almanac website so they can read it too.

20 Douglas { 05.18.16 at 7:08 am }

Since I started reading the almanac, I’ve been learning more ad more. Putting what I’ve learnt/comparing and observing to nature itself is fascinating. I grow better herbs now.thanks

21 John Rutledge { 05.18.16 at 7:06 am }

So why is it that the 3rd full moon (that every season has) and not the 4th ( which is an unusual and uncommon event) is called the “blue moon”?

22 Elsa Canino { 05.18.16 at 6:48 am }

Thanks For That information. I just le arnés son thing new and Very interesting.

23 Mary Galindo { 05.18.16 at 5:51 am }

Thank you. Now I found out something I always wondered about.

Leave a Comment

Note: Comments that further the discussion of the above content are likely to be approved. Those comments that are vague or are simply submitted in order to promote a product, service or web site, although not necessarily considered "spam," are generally not approved.

If you notice a hole in the upper left-hand corner of your Farmers' Almanac, don't return it to the store! That hole isn't a defect; it's a part of history. Starting with the first edition of the Farmers' Almanac in 1818, readers used to nail holes into the corners to hang it up in their homes, barns, and outhouses (to provide both reading material and toilet paper). In 1919, the Almanac's publishers began pre-drilling holes in the corners to make it even easier for readers to keep all of that invaluable information (and paper) handy.

Reading Farmers' Almanac on Tablet with Doggie

Don't Miss A Thing!

Subscribe to Our Newsletter and Get a FREE Download!