Steve Kruse, Master Gardener and owner of Kruse Farm & Garden Supply uses our castings regularly in his greenhouses. Last year he did a test using 3 rows of his tomato plants with different mixes, one row with no earthworm castings, second row with earthworm castings only and the third row with his own mix and earthworm castings.
He became a believer.... here was his views on the test:
Here is my info regarding the results of my tomatoes in the greenhouse using your worm castings.
I have been growing tomatoes for several years in my greenhouse. I grow them in containers using a mix of potting soil and compost material. While the plants grow well, and I get a good crop of tasty tomatoes, I have always felt that the tomatoes could be better. This season I planted the tomatoes in my usual mix and started growing while still looking and trying different products to get the great tasting tomato and large crop I always expect. The tomatoes were off to a great start, and looked very healthy. In May I meet Brenda McBryde and she told me about worm castings. I decided to try her castings on one row of my tomatoes. In one of my greenhouses I had three rows of tomatoes growing. For the experiment I left one row to grow with my normal fertilizer method, one row with my fertilizer plus worm castings, and the third row had my fertilizer along with a liquid organic soil builder.
When I first applied the castings to the test row all the plants were already growing very well. I applied about two pounds of castings to each plant the middle of each and every month starting in mid May. The plants are very healthy and growing like never before. The plants growing with my fertilizer only look good but the plants with the castings and the organic soil builder are larger in size and have produced a larger and tastier crop. All my plants in the greenhouse this growing season have grown better than any of the years I have been growing. I think this is due to the cooler than normal temperatures. However, the worm castings along with the organic soil builder has produced healthier plants, more pounds of tomatoes, and the crop has produced for a longer period of time. I will defiantly use more worm castings in the future.