Will a potted plant grow bigger if earthworms are added to the soil?

Answer 1

There are several theories on this subject, one research is advocating the removal of earthworms in our forests, I will provide a few links for you to decide.

Please see related links below.

Not likely.

Earthworm effects on soil fertility are the subject of decades of research (including my PhD thesis). Here are a few scientific articles demonstrating the plants do grow better in the presence of earthworms. You can Google scholar the names and dates of the authors to get the abstract of the articles. The full articles are usually available through public library internet connections (they have subscriptions to the scientific journals).

In the field, earthworms at a density of 40 to 80 g / m2 increased the efficiency of
organic fertilizers by increasing the N mineralization rate of the ingested material
(Pashanasi, 1992). Binet (1992) estimated N release from rye grass processed by
earthworms at 0.13 mg of N per gram earthworm per day. Birch seedlings planted in
soil with earthworms had more leaf and stem biomass than those grown in pots without
earthworms (Haimi, 1992). Nitrogen uptake increases in the presence of earthworms
(Ruz-Jerez, 1992, Edwards, 1998), and so does soil porosity (Edwards, 1998).
Earthworm casts applied to soybean plots increased plant dry weight by 40 to 70% (Lui
et al., 1991) and plant yield was increased by 36% in the presence of earthworms
(Pashanasi et al., 1996). Increased nitrogen uptake in the presence of earthworm casts
was also reported by Zhao et al. (1988) and Tomati (1994).