preparing and amending vegetable garden soil

As I sat inside this past week-end staring out at my frozen raised vegetable beds, I at least got time to plan exactly what I am going to put in them once I get the chance... (I'm trying to look on the bright side, here!)  Since a few of you recently sent in questions regarding this topic, I thought it was worthy of a post.

 

Last spring I emptied the contents of my compost bins (which also contained quite a bit of soil) into these raised beds (above) and topped them up with leaves.  This spring I will be adding vermiculite, turning them over and then topping them up with good topsoil.  According to Mel Bartholomew, author of Square Foot Gardening, a good vegetable garden soil should be made up of at least 25% (up to 50%) of soil amendments such as compost or leaf mold.  Another good rule of thumb is to add 10 - 20% by volume of coarse vermiculite to a new vegetable garden for good moisture retention - vermiculite is like a sponge.

But once you've prepared your initial soil, how do you keep amending it each year to maximize production?  Mel Bartholomew has lots of recommendations.  He says (and I agree), "trying to grow crops in any kind of soil without constantly adding organic matter is sheer folloy and a waste of time, no matter how much fertilizer you add to it.  On the other hand, to garden in soil that is rich in organic matter but contains no added fertilizer is not only possible but also very practical."  He recommends:

• add a trowelful of compost or other organic soil builder after you harvest each plant in your garden - this will probably mean you are amending at least 2x per year, maybe even 3 or 4
• supplemental fertilizers to use during the growing season need only be of 2 types: a high nitrogen fertilizer for leaf crops (eg. lettuce, spinach, chard) and a high phosphorous and potassium fertilizer for root and fruit-bearing crops;
• you can add dry fertilizers when the soil is prepared for planting, plus once a month as crops are growing, in the form of a pre-packaged organic mix, or make your own, see recipes below
• heavy feeding crops (eg. brassicas) will also benefit from supplemental watering with compost tea, fish emulsion, or seaweed/kelp solutions

Basic, all-purpose fertilizer recipe

• 1 part bloodmeal
• 2 parts bonemeal
• 3 parts greensand
• 4 parts composted leaf mold
• approximate NPK value: 2.6 / 4.9 / 1.8

High-nitrogen fertilizer recipe

• 3 parts bloodmeal
• 2 parts bonemeal
• 3 parts greensand
• 4 parts leafmold
• approximate NPK value: 4.6 / 4.3 / 1.6

I haven't been nearly as diligent as I should have been in the past and still got decent results, but this year I am vowing to follow his recommendations to try to maximize my harvest. What do you do in your vegetable garden?  Please share in the comments section below.

For more tips on growing vegetables in Calgary, see my previous posts:

• When to start planting vegetable seeds in Calgary
• Vegetable gardening in Calgary 101
• Vegetable gardening tips - notes from Square Foot Gardening
• What you need to know about building raised bed vegetable gardens
• resources specific to growing vegetables in Calgary

If you would like a beautiful and successful vegetable garden that nourishes your body and soul, view My Services for consultation details.

Comments

[SJ]

What is greensand?

[Janice Miller-Young]

Its an organic fertilizer that comes from rock and is a good source of potassium and also helps soil retain moisture.  I have actually skipped this ingredient but only cause Im in a hurry to get going - I may add it to the top layers of my soil later.
Let me know if you use it and like it!
Janice

[Hanna]

Help! Where can I find blood meal. The deer are loving my tulips a little too much!

[Janice Miller-Young]

Any garden centre-y place should have it!  This includes places like GreenGate or Sunnyside right through to Canadian Tire or Home Depot.

Good luck!
Janice