Managing pests and diseases through natural means

Insect pests and plant pathogens are a challenge for every farmer and the temptation to wipe them out is strong. It is tempting to always reach for chemicals. In the short-term, chemicals may provide a quick knock-down to the attackers, but they may also kill beneficial organisms.

In the long-term, you expose yourself and the environment to toxic chemicals, and risk disrupting the natural ecosystem in your garden. Pest and disease occur mainly due to wrong cultivation practices.

Hence to avoid pest and disease occurrence, the following agricultural practices should be taken into consideration under “Prevention is better than cure” ideology.

Grow your plants in healthy soil. Essentially a healthy fertile soil can only give good plant health. Fertile soil is the most effective method of preventing a pest or disease outbreak.

Plants growing in poor soil with nutritional deficiency will be susceptible to pest and disease attacks. Healthy fertile soil will impart power to plants to resist pest and disease attacks.

Hence, vitalising and improving the soil by suitable organic and bio-dynamic agricultural methods is critical. It may take years to achieve this, but even the poorest soil can be made fertile using organic methods. For this purpose continuously apply compost manure to improve nutrients levels, soil structure and water holding levels and practise green manuring.

Insects and diseases will be attracted to stressed, damaged or otherwise unhealthy plants, so the key to preventive control is taking good care of your plants. That means paying close attention to them and providing the conditions they need for healthy, vigorous growth.

Quality of the seeds and seedlings: Quality of the seeds has a significant role in pest and disease incidences in a crop. Hence, it is important to get good quality seeds and seedlings for sowing and planning respectively. If quality seeds are not available, the quality of available existing seeds can be improved by proper selection of mother plant.

Quality seeds can only produce a healthy and vigorous seedling that has an inherent capacity to resist any pest and disease attack and give good yield. With the help of the quality seeds, good seedlings can be raised. Then while buying the grafted seedlings make sure that the seedlings are raised from good and selected mother plants. There is no point starting with weak or diseased seedlings.

Timed planting: Insects usually appear at about the same time every year, so you can try to schedule your plantings to avoid the heaviest feeding stages. Keep records to gain familiarity with these patterns in your own region and microclimate.

 

Resistant varieties: Certain varieties or cultivars show a strong natural resistance to pests and/or disease. Plant breeders also select for disease and pest-resistant characteristics. Seed packets and plant labels usually indicate these desirable qualities. You may also contact your local extension officer for information.

Adjust the spacing: If plants are spaced too closely they are a lot more susceptible to fungal diseases such as grey mould or mildew. If you want to lessen any potential problem you can always space your crops further apart. This increases the airflow through the crop and reduces the incidence of fungal diseases that thrive in more humid conditions.

Make garden cleanup a routine: Leaving old vines, tomato plants, and similar debris in your garden after the harvest ends is like putting out a welcome doormat for pests and pathogens. Many insects stay in such debris, and they will get an early start nibbling on your plants the following season. Many plant pathogens also live in the soil year-round. The heavily infected plant parts should be burnt. If your vegetable garden is messy it is much easier for pests and diseases to spread much faster. Remove and dispose of any diseased or infested plants. Turn other debris into the soil or put it in your compost pile.

Loosen the soil with a fork or spade so that any remaining eggs, larvae, or pupae will be exposed to birds and cold temperatures. Mow or remove the weeds around your garden, since they can also harbour insect pests.

Rotate your crops: Many insects and disease-causing organisms stay in soil near their host plants. If you grow the same plant (or a related one) in the same place the following season, you give those pests a big head start.

Crop rotation can reduce insect damage and minimise exposure to soil borne disease organisms. The rule of thumb is, wait at least two years before planting the same or related crops, such as broccoli and cauliflower, in the same spot.

Brassicas, potatoes, tomatoes, and onions are particularly vulnerable to disease problems when planted in the same place year after year.

Crop rotation can also help keep soil nutrients in balance. A first-year planting of heavy feeders, such as tomatoes and lettuce, can be followed by legumes, such as peas and beans, which return nitrogen to the soil. The third year, you could let the soil “rest” by planting light feeders, such as carrots or beets.

Encourage diversity: A garden with good biodiversity is a lot less prone to sudden attacks of pests and diseases as there is a balance of pests and predators.

To increase the biodiversity in your garden, put smaller groups of plants throughout the garden, rather than planting all of your potatoes, say, in one place. It will be more difficult for pests to converge on the whole lot.

 

Inter planting herbs and flowers is another effective way to protect your garden: Some plants, such as marigolds, seem to repel insect pests. Others, such as mint, attract beneficial insects that prey on garden pests.

Mixing some of these plants into your vegetable garden will foster a more diverse and naturally healthy ecosystem.