Using alfalfa as a cover crop between garden plants has resulted not only in improved soil but also in hosting a variety of beneficial critters to control pests.

I love the insects1 in my garden! Each day I am excited to see the growth of the garden and who is playing in it. Last year I experimented with using alfalfa as a cover crop between my plants. Not only did this eliminate space for weeds, improve the soil, provide a wind brake, host a little shade from the Texas sun, but it provided cover for beneficial insects. I am impressed with the results, and continue to use it.

Some of the alfalfa made it through the winter, and some I replanted in early spring. Organic practices, such as abstaining from the use of chemical insecticides, is not always easy. Last year I had an infestation of the dreaded blister beetles and rather than spraying the garden with chemicals, I manually picked out what seemed like billions of these stinkers. If you have ever been hit with blister beetles you know how they can be a test of patience and resolve.

This spring I was really excited when I found a handsome crew of beneficial insects in my garden. The neighbors might have been surprised to see me with a big smile, yelling YES, bugs in the garden!” then doing a little victory dance. Maybe these critters overwintered 2, or maybe they just found the garden, whatever the case, I am grateful for their presence.

Here are some of the stars.

  • A Lady Beetle (Coccinellidae) larva. Fast moving and hard working.

Lady Beetle (Coccinellidae) larva

  • A Lady Beetle (Coccinellidae) pupa. Sessile (immobile) but still working hard, in this case working on becoming an adult.

Lady Beetle (Coccinellidae) pupa

  • An adult Lady Beetle (Coccinellidae).

Lady Beetle (Coccinellidae) adult

  • A spider taking care of a caterpillar pest. There is also another visible lady beetle larva.

Spider finds a meal

  • Here is what looks like a Robber Fly eating a Leafhopper.

A robber fly eating a leafhopper

  • These guys are ambitious. I was cutting the grass when this rather large spider came out to see if I was fit for a meal.

A large and ambitious spider

  • The invertebrates are not alone, I have other helpers too.

A toad at the buffet

I am so happy to have my Beneficial Bug Brigade. I hope they continue to enjoy their stay. :-)

What beneficials do you have?

  1. Arachnids too. 
  2. Coccinellidae adults can do this, and these specimens sure made an early appearance… 

I love me some green manure! Specifically, I love nitrogen fixing plants like alfalfa. Do you think your only choice is to grow plants for harvest, or cover crops? Why not both?

I built a new garden space this year to add to the Liberty Garden. I use the term Liberty Garden to refer to all the outdoor space devoted to growing useful plants at my home. The new garden zone is a small raised patch surrounded by a wooden frame. It is only about twelve by six feet1, so space is precious. The plan was to completely fill up the frame as is done with square foot gardening. Well, things do not always go according to plan. When it became time to plant, I was not ready with enough plants to fill the space. In fact as I write this I still have Amaranth2 and other babies in the windowsill nursery.

Since I did not have enough plants, and because I like to experiment with things like this, I planted what I could and filled the remaining space with alfalfa. Experiment is not the right word here as there was nothing scientific about this process, a gamble would be a better term. I selected alfalfa because it has deep, robust roots to really work the soil, it is a nitrogen fixer so a nice organic nitrogen source, is non-toxic (actually rather nutritious), has flowers that attract pollinators and other beneficial insects, and other nice qualities. The following is a picture showing part of the patch.


The results have greatly exceeded my expectations. The alfalfa has crowed out weeds, improved the soil and attracted pollinators as I hoped, but it has also attracted other beneficial insects such as lady bugs. You may see one or two if you look closely in the following picture.


What I did not expect was a beautiful herd/swarm/crowd/abundance of really impressive spiders. I do not have any pictures of them but they could be what is pictured at the following link. They must be a hunting spider of some kind as I have not seen any web. They are bigger than the wolf spiders I typically see; these measure about the size of a silver dollar. The garden patch has been nearly pest free with these babies patrolling. The spiders must need a little cover from birds as the population has been richer when the alfalfa is not trimmed lower than one foot.

Another pleasant surprise has been how the alfalfa has provided a wind brake for the tender young plants. Once the plants get to be about ten inches tall they are able to handle the sometimes brisk wind. Until that time, they have alfalfa to protect them. The following is a picture of some sage happily thriving surrounded by alfalfa.


The net is that I am really pleased with the alfalfa test. Filling the available space with alfalfa provided all the benefits I hoped for and more.

  1. That is about four by two meters 
  2. This is the second attempt at getting hardy Amaranth babies.