Here at Hormex we never shy away from using as many all natural inputs in our gardens as possible. From non toxic insecticide alternatives like table salt rings around plants for slugs and snails (use wisely), or utilizing less desirable techniques like fish heads and macerated fish guts tilled into the soil for added nitrogen. And as many of you may already be well aware of the wide ranging benefits that come from sprinkling eggshells around the garden, it’s always fun to review for those that already know and great info for those who don’t.
Eggshells have a number of uses in the garden and just as many application methods; whether they are added directly to the soil, composted or processed into a sterile powder. And while the benefits completely outweigh the risks, the most important thing to remember is that when adding food products directly to the garden you are always going to run the risk of inviting pests. The level of tolerance provided for some uninvited guests over others will vary, depending on their particular interests in the surrounding plants, i.e. rats and mice are more harmful to your tomatoes than cockroaches or certain waterbugs. So keep that in mind with unrinsed shells as they will contain residue from the leftover egg white (albumen) that sticks to the shell. It always proves to be a welcome treat that’s equipped with its own bowl which every rodent will love. Conversely when placed around the perimeter of the garden the smell of egg albumen emitted from the littered shells can be a very strong deterrent for deer.
As an insecticide and pest deterrent eggshells are also highly effective in the control of slugs and snails, the sharp edges prove to be too abrasive on their soft bodies. This is most effective when the shells are powdered and dusted around the plant. Concurrently scattering the powdered shell flakes around and on affected plants will get under the exoskeletons of beetles whereby the shell pieces cut into the exposed flesh underneath their own shells and begin to fester, ultimately killing them off one by one.
In terms of nutrient input, eggshells add much needed calcium as their comprised of primarily calcium carbonate CaCo3. Of course their calcium rich composition also has the added benefit of being extremely alkaline, which will help to to lower soil acidity when needed.
Preparation once again its all dependant upon the desired application. It is recommended for all uses other than composting that you sterilize all used shells by boiling them for up to ten minutes. For a talc like powder place cracked shells into a coffee/spice grinder, and grind into a fine powdery consistency. This creates a great way to incorporate the powder as a soil mix, to be added along with the leftover coffee grounds for increased nitrogen. If you don’t have a grinder or mortar and pestle the same effect can be still be achieved For a much more broken down shell that will prove to be like shrapnel for beatles, take rinsed shells and place them into a zip-lock bag, lightly press on shells with the bottom of a glass until the shells break up into tiny shards.
Now for some of our vegan friends that often have valid reasons for not wanting to incorporate Chicken eggshells into their garden. Be they for ethical reasons tied into factory farming and or just the consumption of animals in general, which can create a strong objection to utilizing such things within the garden. One option is to source shells from friends and family that use organic/free range eggs; though you may find that many people are not enthusiastic about the idea of storing broken eggshells. However the prospect of fresh fruits, vegetables and flowers in exchange is usually a great selling point. The same concept obviously applies for small farmers and sourcing large quantities of shells from restaurants that they have relationships with. Another option, although more rare is to seek out a poultry fancier that is perhaps raising Silkies and feathered footed Cochins as ornamental birds and using their fertilized eggs for breeding new chicks; this way all that is being used is a discarded shell. Or just stick with diatomaceous earth.
With Spring on the horizon now is the best time to start preparing your soil and preparing by also organizing any additional ingredients for future inputs. So what better time to start tossing egg shells into the yard instead of the trash. And remember it’s not only chickens that lay eggs, so don’t limit your options when on the search for fresh ovums.