By Nadine Keller, Finder Blogger: The Green Thumb, and founder of www.aerospringgardens.com
All creatures great and small need to eat, and in the process of feeding, bugs can wreck havoc to your garden, even completely destroy it. As with all things in nature, there is a balance.
A concentration of edible plants aka your garden, is like a smorgasbord buffet for some of the most annoying garden pests. Scale insects suck sap out of plants and are probably the most common to be found in the everyday edible garden. Aphids, Whitefly, Mealybugs, Scales, Spider mites, Thrips and Leafborers are the names of the most notorious members of this family of sap suckers.
Here’s how to deal with them.
1. Be on the ball
When you are in the garden, pay careful attention to the leaves, especially the underside of them, the top shoots and the stem of the plant. Damaged or curling leaves are an indicator that a plant may be infested with bugs, so look closer for eggs, larvae and adult insects, which vary in colour according to species and host plant. Check the junctions at stems, as mealybugs park their tiny eggs in those nooks. Look for bronze stippling and white or yellow leaf spots. If a plant has already been severely infested and it’s neighbours only look like they have been minimally exposed, I kill patient zero. This is easy to do in hydroponic gardening by just throwing out the offending plant but requires a little digging and clearing in a soil garden.
2. Use water
If you have just started your garden and your plants are small, you shouldn’t apply any pesticides to them, even if they are natural. They can suffocate and stunt their growth, sometimes even kill them in my experience. So the best way to curb an initial infection if detected, is to spray the plant with a mist of water, ensuring that as many of the insects or larvae are removed from the plant. Gently spray it from top to bottom, between the stem junctions and underneath the leaves, giving it a good wash in the early morning before the plant is exposed to any harsh sunlight. You want to do this because tiny water droplets act like magnifiers in direct sunlight and cause leaf burn.
3. …Or soap sprays and horicultural oils
To keep pests on their toes after that, use Insecticidal Soap Sprays or Horticultural Oils like Neem Oil. Spray just one leaf first and wait a day to see how it reacts before applying to the entire plant. If the leaf looks fine the next day, apply the spray to your plants, every three to five days as a single application may not kill or remove them all. Repeat this process if it’s rained and keep checking between sprays if you are winning the war on bugs.
You can buy or make your own soap and horticultural sprays from ingredients at home, quite easily and quickly. To start a simple 2% insecticidal soap spray, use a pure liquid soap like Castile from Dr Bronners. Don’t skip this step and use dishwashing liquid or handwash, because it’s the fatty acids contained in natural soaps that do damage to the soft cell bodies of the bugs. Mix 1½ tablespoons of liquid soap with a litre of water in a clean spray bottle, shake and you are ready to super soak!
I like to do a variation of this soap spray, which contains garlic and chili and combats aphids, mites and caterpillars quite effectively. Puree 10-20 chillies, three cloves of crushed garlic with a litre of water in a blender. Strain the mixture and then add the soap and the other litre of water. You can separate and store the solution for about two weeks in the fridge. Be very careful not to overspray your plants and make sure to test patches of leaves before doing battle with the sprayer. And beware not to accidentally spray yourself and to wear gloves when preparing this concoction.
Neem Oil is a non-toxic, plant derived Horticultural Oil which you can get in concentrate from any garden centre. It’s used as an organic insecticide, fungicide and miticide, so it offers quite a broad spectrum of protection and treatment for plants. Neem Oil deters insects from feeding on your plants, acts as a repellant and interferes with the insect’s hormone systems.
You can find the concentrate solution of Neem Oil at most garden centres and at Jothi Store in Little India. Use a weaker solution for maintenance and add a touch of liquid soap to the mix. Some plants don’t like Neem Oil at all eg. Zucchini, so spray a test patch leaf before going all out. You can even spray and treat the soil, as the plant will take it up systemically which deters insects from feeding even more.
Because the growing season in Singapore is all year round, you will need to be on your toes constantly if you want to maintain a bug-free edible garden. For more information on growing your own food hydroponically or aeroponically with our vertical gardening system Aerospring Gardens, find out more at and contact us at www.aerospringgardens.com or www.facebook.com/aerospringgardens.
About Nadine Keller
Raised in Singapore by German-Singaporean parents, Nadine has lived in Sydney, New York and Paris. She returned to her Singapore roots in 2008, and recently went out on a limb with partner Thorben Linneberg to offer Aerospring Gardens, a cool, vertical growing system – perfect for compact condo and HDB living. Nadine will help you learn to grow tricky plants like tomatoes, cukes and more.