Aphids - Aphids feed on the juices of plants, attacking leaves, stems, buds, and flowers. They are particularly fond of new growth. If you think you have aphids, check the undersides of your leaves for tiny, pear-shaped bugs, which can come in a variety of colours. Other signs of aphid infestations are stunted, curling, yellowing, or generally misshapen leaves. The undersides of the leaves, stems, and below the plant itself may be sticky from a residue left by feeding aphids called 'honeydew.' This sugary liquid can attract ants, as well as allowing for a fungal growth called sooty mold, which will cause affected areas to look black. More information about aphids.
Thrips - Thrips are tiny, bugs which suck the life out of plants. Their damage can look like speckles, streaks, or white, dying patches. If you think you have thrips, it can be difficult to tell as they are the sizes of splinters. You can shake your plant over a white piece of paper, where they will be more visible if they fall off. Thrips may be attracted to yellow or blue sticky traps, which can help control populations. Insecticidal soap or neem oil can also be sprayed onto the surfaces of leaves to kill bugs. It's also possible to introduce/encourage beneficial predatory insects to come to your garden, such as ladybugs, which will eat the thrips. Further information.
Slugs and Snails - They will eat almost anything in your garden, leaving behind ragged holes, cut stalks, and scalloped leaf edges, so keep an eye out for their shiny, slimy trails if you suspect slug/snail damage. It is possible to trap slugs in shallow dishes of beer left out overnight. Slugs can also be trapped by laying pieces of wood or cardboard out near your plants where the slugs will take shelter in the morning - giving you the perfect opportunity to scoop them up and evict them from your garden. Further information.
Rodents - Mice, rats, and squirrels love to nibble on seeds, young plants, and growing vegetables. Physical barriers are effective at preventing rodent damage, such as building mesh cages around your most vulnerable plants. Rodents can also be trapped using humane traps and relocated to another area such as a forest. Further information.
Attracting beneficial insects: The more biodiversity you have in the garden, the more things will be attracted. Plant early-blooming flowers to draw insects who eat nectar and pollen, so that they will lay eggs and produce their important, insect-eating larvae. Remember that chemical pesticides will kill insects in your garden indiscriminately, so you will lose the beneficial bugs as well if you resort to harsh measures.
Bees - Bees are important pollinators, helping to ensure that your fruits and vegetables will grow, and that your flowers will produce seeds. They are sensitive to chemical interventions, so be careful with what you put in your garden!
Butterflies - Not just a pretty face, butterflies also act as pollinators in the garden.
Wasps - While incredibly annoying, wasps also do act as pollinators as well as predators.
Hoverflies (fake wasps) - The tiny, wasp-like insects who hover like hummingbirds are not only pollinators, but their larvae are good predators, eating aphids, beetles, and thrips.
Ladybugs - Ladybug larva look like scary little crocodiles, but they can can eat up to 40 aphids per hour!
Spiders - Spiders will happily eat smaller insects in the garden.
Powdery Mildew - A fungal disease which will make your plant appear as though it has been dusted with flour. Will spread on plant if not controlled. Some ways to mitigate damage: prune infected areas off the plant - additional airflow will also help. Move plants to sunnier areas if possible to reduce humidity. Mix a small amount of baking soda in water and spritz onto infected leaves. Further details.
Rust - A fungal disease which causes yellow-orange blisters to appear on your plant. It occurs more easily in mild, damp conditions. Once a plant has been infected with rust there is no easy treatment - the best option is to remove infected leaves as soon as they appear. Splashing the leaves with water can spread the spores to other leaves/plants. Further details.
“If things aren’t eating your plants – your garden is not truly part of the ecosystem”
If your garden is full of bugs, you are doing something right. Insects are the biological foundation for all terrestrial ecosystems. They are an essential component of how a garden grows and remains healthy. Sometimes – they eat your plants.You will lose things to aphids, slugs and snails, cabbage moths and other hungry critters. It might make you cry but it does not mean you are doing something wrong or failing.
Scroll along the following photos to see some of the tactics I employee to keep a balance so I still have lots of garden to enjoy myself while keeping my soil and biodiversity healthy:
Too many basil seedlings? Probably not…
Plant more seeds then the number of plants you know you need. If some get eaten, you still have lots to enjoy. If you have too many – give them away to friends and neigbours.
Aphid city! Realize that you will lose plants and it is fine. You are not failing. These kale plants are flowering and on their way to producing seeds. For whatever unknown reason a few have become completely covered in aphids.
That is fine! Plants at the end of their life cycle are more likely to be susceptible to pest damage. I don’t need that many plants to make it through to the seed stage to collect what I need. And, these aphids will likely attract ladybugs which are a great help to a gardener. Many insects are very good at controlling pest populations so seeing insects on your plants should not necessarily be a cause for concern. I will keep and eye on it and I can decide to yank and compost these at some point but for now… I will leave them.
I moved these pansies out of the ground where they were being devoured by slugs and into a pot. I am hoping it will provide a more controlled environment where I can catch the slugs before they eat all the flowers.
Try to keep plants out of extreme stress. A healthy plant has a better chance of surviving and less chance of attracting pests. Water regularly, feed occasionally, give an appropriate amount of sunshine. If something seems very unhappy – move it!
The more biodiversity you have the better. Period. Grow a wide variety of plants. See what works and what doesn’t. Keep notes if you want for next year. If you fail – try again in a different spot in a different year. Having a wide range of plants will attract a wide range of insects and they will do a large part of pest control amongst themselves.
If there is something you really want to grow and you are having trouble with pests – employ natural pest solutions whenever possible! For myself, I would rather give up growing something specific rather then risk disruption my complex garden ecosystem with a chemical pesticide.
Companion Planting – some plants deter some insects and attract others. Here I have planted Cabbages next to dill and marigolds. Both these plants should help to deter cabbage moths.
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