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chickencoupe1

Calculating Garden Space for Onions

chickencoupe
9 years ago

kim brought it up and I must really think hard to confirm just exactly HOW to come up with necessary garden space. If anyone has simpler suggestions that'd be great. here's what I come up with - the hard way, of course.

Dixondale suggests the bunches are anywhere from 50 to 75 plants.

I use 65 plants per bunch as an average.

Since I grow organically, I don't need fertilizer trenches as Dixondale suggests . The Bonnie plant site recommend onion bulb spacing at 6" . I want to do 6" because I have clay soil and they may need plenty of room to grow big and juicy. Closer plantings are permissible. They will still grow, but experts suggest bulb size maybe limited. Instead of planting in rows with fertilizer trenches, I will plant them 6" apart from each other in every direction.

So, 6" spacing needed for each plant.

1 bunch = 65 plants

1 plant = 6 sq"

65 x 6" = 390"

390" divided by 12" = 32.5sq ft.

So, essentially, I need about 33 sq ft feet for every bunch I ordered.

Now, I want to include an additional 3" border around the bed. This depends on at least one side/length of your garden bed. Let's just pick a garden bed length: 10' x 4' What we're calculating is the average square foot needed per bunch and the garden bed can be adjusted, later. Add 3" to the overall dimension of the garden bed. You have a garden bed of 10' x 4'. You will multiply the length and width by 3", individually. (You're calculating the Area of that little rectange on the edge that is 3" wide by 10' long.) For example one side is 10', so you would calculate 10 x 3" = 30". Then, you would calculate the 2nd side which, in this case, is 4'. So, 4 x 3" = 12" for the second side.

Now, you have a total of 42" (30" + 12") to add to your garden bed square footage to include a border. That's 42" divided by 12" = 3.5 sq ft.

So, your actual garden bed for one bunch of 65 plant will need 33 (sq ft) feet plus an additional 3" (multiplied) per foot of length or width. In this case, you need 3.5 (sq ft) to include offset from the edge of the bed. 33 + 3.5 = 36.5 sq ft.

Total = 36.5 sq ft for one average bunch of onion sets.

(Did I do that right?)

Don't know how big the bed is to be?

Area = Width x Length.

SO, if you know you have 65 plants.
And if you know one side. Let's say you want a 10' bed on the long side.

You have the length and the area. like this:

W x 10' = 65 plants, or one bunch which requires 36.5sq ft

Divided 36.5sq ft by 10

W = 3.65 feet or just under 4 feet.

Your bed needs to be 3.65 feet by 10 to accommodate fully. Basically, 4x10 for one bunch of onions, if your bed is, at least, 10 foot long.

You can substitute numbers in these equations to accommodate different size beds or areas or plant sets. Hope I did this right, cuz it's how I'm figuring mine. lol

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