How Many Flowers Will I Need to Make a Flower Wall?

Pinterest, Instagram and other social media sites are full of swoon-worthy floral arrangements.  One of the most popular, is the gorgeous Floral Wall.  Pictures upon pictures of celebrities, party goers and brides feature floral and/or greenery walls as a backdrop for their red carpet, ceremony or other photo opportunities, resulting in the explosion of these types of images everywhere you look.

Given their incredible popularity, our 48LongStems florists are often asked, “How many flowers will I need to make a flower wall?”  Again, the answer is different depending on the size of the wall, the size of the flowers you wish to use, and if you wish to use greenery and flowers.  But here is the how we come up with the answer to this question.­

As with our other “How Many Flowers Do I Need?” blogs, it all comes down to math. We know, math, yuck.  You thought once you were done with school, you could forget all that geometry stuff, right.  Wrong.  However, the good news is, we’ll show you how to become a floral math genius and it doesn’t require too much work.  We promise – you got this!

Just like determining how big a couch, or rug, or table or bed you can fit in your home, you will have to gather a few measurements.

First, you will need to know the size of wall you are trying to cover – 8 foot high by 4 feet?  8 foot high by 5 feet?  You get the idea.  Now convert your feet into inches (remember – there are 12 inches in a foot – see not so hard).

For example, an 8’ x 4’ wall is 96 inches x 48 inches.  An 8’ x 5” wall is 96 inches by 60 inches.  You get the idea.

Now, you get to dust off that old geometry.  You need to determine the overall square footage of your wall.  In other words, Length (L) x Width (W).  The official math formula for a square is A = L x W 


So, an

8’ x 4’ wall = 96 x 48 = 4,608 square inches

8’ x 5 wall = 96 x 60 = 5,760 square inches


Next, you will need to know the diameter of the flower bloom you wish to use.  48LongStems shows the average size of a full bloom under the Description tab found at the bottom of every flower product page.


Standard Roses or Carnation in full bloom is approximately 2 inches in diameter.  Large headed mums, are generally 3.5 inches.  We’ve chosen these as examples because they are hardy blooms that do well out of water for several hours.  Many flower walls do not include a water source, so you need to select flowers that will hold up well for the entire day of your event without needing water. 

Returning to our floral math –

Determine the radius (that is half the size of the diameter) for the flowers you have selected

Fully bloomed Standard Roses and/or Carnations – Diameter = 2 inches;  Radius = 1 inch

Large Headed Mums – Diameter = 3.5 inches;  Radius – 1.75 inches

Now comes the fancy math.  We need to calculate the average area of each flower.  Sounds tricky, but it’s just this:

Area of each flower = Pi (you know, 3.14159) x the radius of your flower, squared (or r x r)

In fancy math language it looks like this:  Area of each flower = 3.14159 x r2  (For you true math nerds out there, and you know who you are, we know it’s really this: A=πr2)  Don’t you feel smart now!

Now to make it easy for the rest of us:

For a full bloomed rose/carnation:  3.14159 x 1 x 1 = 3.1416

For a large headed mum:  3.14159 x 1.75 x 1.75 = 9.6211


Finally, Divide the wall area by the flower area.  Again, this will be determined by the size of wall you need to cover, and the size of the flower you are using.  Using 2” roses and/or carnations for the wall size as a guide:

An 8’ x 4’ wall = 4,608 square inches/3.1416 = @1,467 flowers. (We’d round up to 1,500, to be safe)

An 8’ x 5’ wall = 5,760 square inches/3.1416 = @1,833 flowers. (Again, round up to 1,900 – 2,000)


Using a large headed mum or other 3.5” bloom you’ll get the following:

An 8’ x 4’ wall = 4,608 square inches/9.6211 = @479 flowers. (We’d round up to 500, to be safe)

An 8’ x 5’ wall = 5,760 square inches/9.6211 = @599 flowers. (Again, round up to be safe)

Key Florist Tip: The size of your bloom will greatly impact the number of flowers you will need, as well as the overall cost.  Generally speaking, the bigger the bloom, the lower the cost (unless you choose a really pricey big headed flower).