Building a self-sustaining farm: soil and pest management insights

The ultimate goal is to have a farm that is almost self-sustaining and requiring very little input and becoming highly productive. I would like to share some milestones in my journey before achieving this goal.

Although I started off with what I perceived to be virgin soil, I discovered that it was rather nutrient deficient and I had to apply agricultural lime, potassium and phosphate.

With regard to potassium, one should apply potassium sulphate and not potassium chloride, despite the big difference in price.

Cattle manure is high in potassium and usually contains 3% to 4%, which means that you could use enough to counter the need to use K2SO4.

In the initial stages you may have to apply some chemical fertiliser, even if it is only LAN.

Improving the soil

My soil was low in organic matter despite being virgin land and I experienced white grubs, which are the larvae of chafer beetles that fly at night in midsummer and are attracted to lights.

These would feed on the roots of my Brassica crops and caused a fair amount of damage. I expected them to become an even bigger problem when the organic matter in the soil increased, but to my amazement, as the humus content of the soil rose, the grubs simply disappeared and I have not had one plant damaged in many years.

I also had a fair problem with the larvae of the spotted maize beetle, which are soil dwelling and also caused some damage.

I used to have swarms of the adults that would cause problems by eating the flowers on my peppers and also attacked the flowers on my cucurbits, affecting pollination. Now I have no problem.

Perhaps the pest that caused the most damage was root-knot eelworm (Meloidogyne spp). I had to fumigate the soil where I had planted beans or I would have had a crop failure.

Many plants would be dead before even reaching flowering stage. As I was breeding beans and would have 60 to 100 varieties in a trial, I also had to apply a fungicide to half of every variety to control bean rust.

I had to leave the other half to be able to determine the level of resistance. I thought I would have to adopt this procedure always.

However, as the organic content of my soil increased I had the dilemma of having no rust developing, which made it difficult to determine the degree of rust resistance.

The root-knot problem also completely disappeared when the organic status increased and I was able to grow beans without having any eelworm damage or rust.

Eelworm

With regard to my tomato breeding, the eelworm problem was so severe in the beginning that varieties without the gene that confers eelworm resistance would be dead before even beginning to set fruit.

I had to plant the marigold variety Tangerine prior to planting tomatoes to eliminate this pest. I tried some organic products as well but had little success compared with the marigolds.

The marigolds act as a trap crop by tricking the newly hatched L2 eelworm larvae to think that the marigolds are a host crop, but they are unable to produce eggs and therefore the soil is cleared of this pest.

This method even works well against the common lesion nematode (Pratylenchus spp.), but only certain varieties of French marigolds are effective.