Many times, random leaf damage will occur. Other times, you will see bugs actively munching on your plants. Growing outside, you may end up finding out every pest wants to eat your plants!
Here is some issues I have dealt with growing outside:
For more information on cold weather or winter growing, visit my
How to grow in winter page
During the summer heat, many strains can get heat damaged when the temperature reaches over 90oF. Some strains are exceptionally heat tolerant, and can withstand at least 110oF in direct sunlight. There is not a lot to it. Try to shade the plants when it gets too hot, and don't let the soil dry out!
A combination of the below items have saved me through all of the pests and diseases I have encountered throughout the year. I will go over some of the pests and the products below.
I have used this neem oil extract for spider mites, aphids, white flies, and powdery mildew.
Mix 2 TBS (1 oz) with 1 gallon of water, and spray all over the plants. For outdoors, spray in the evening when its starts to get dark. Indoor growers should spray right after the lights go off. Sunlight, or high intensity lights will leave burn the oil on the plants that can damage them.
Don't spray the plants for at least 5 days before harvesting.
Information from the manufacturer:
• For use on ALL fruits, nuts, vegetables, herbs, & ornamentals
• Prevents & controls black spot on roses & powdery mildew
• Controls aphids, spider mites, scale, whiteflies & beetles
• Kills eggs, larvae & adult insects
CONTAINS: 70% Clarified Hydrophobic Extract of Neem Oil
USE ON: Indoor/ Outdoor ornamental flowering plants, trees, shrubs, foliage, vegetables, fruits, nuts and landscapes
As Fungicide – powdery mildew, black spot, downy mildew, anthracnose, rust, leaf spot, botrytis, needle rust, scab and flower, twig, tip blight, and alternia.
As Insecticide/Miticide – aphids, spider mites, scale, whiteflies, beetles, leafrollers, and other insect pests.
Caterpillars will completely destroy a plant if left unchecked. They are usually hidden inside of the flowers, and need to be pulled out. As the caterpillars eat, they leave their waste in the flowers. Rotten flower buds are often the end result.
As soon as you see moth eggs any where on the plant, start using this spray. Mix 1 TBS per gallon of water, and spray in the evening. Usually once per week is enough, but severe infestations may need more frequent treatments.
Growers often recommend not using this for a week before harvesting. Nobody knows the effects of having any residual while smoking it, or if it will just make the buds taste bad.
I have had such severe infestations that I sprayed this on the night before harvesting, and still had a few newly hatched caterpillars while the flowers were drying. When the flowers dry, the caterpillars start to leave since there is nothing for them to eat. All of my plants would have been lost if I did not use this spray.
If you do have to use this late before harvesting, a peroxide wash (below) is a good way to get residual pesticides and caterpillar poop out of the flower buds.
More information on caterpillars are in the video link at the top of the page.
Information from the manufacturer
Safer® Brand Caterpillar Killer II– 16oz Concentrate with B.t.– How It Works
Safer® Brand Caterpillar Killer Concentrate uses a naturally occurring bacterium to kill and control caterpillars and other leaf-eating worms. The caterpillars and worms that are damaging your plants will stop feeding immediately after ingesting the bacterium, which is known scientifically as Bacillus Thuringiensis var. Kurstaki (B.t. for short). Plus, when Caterpillar Killer is used as directed, it has no effect on birds, earthworms, or beneficial insects such as honeybees and ladybugs.
This economical concentrate is easy to mix into a ready-to-use solution. And, because Caterpillar Killer is OMRI Listed® and compliant for use in organic gardening, you know that you’re controlling leaf-chomping caterpillars in a way that fits into your organic garden plan.
Peroxide washing is a good way to help get rid of bug parts, dirt, pesticide residue, caterpillar poop, and even powdery mildew. I often use peroxide washes when the caterpillar season is at its worse.
Use 3% hydrogen peroxide, and soak a branch of flowers in it for 1-2 minutes. Rinse off with room temperature water.
A severe fungus gnat infestation will completely destroy a garden, indoor and outdoor. These gnats lay their eggs in the growing medium (soil, rockwool, etc). When the eggs hatch, the larvae will eat the roots. Fan leaf damage is the first sign you will see.
Fungus gnats love nutrient-rich moist soil. They tend to be worse in spring and fall.
Yellow sticky traps work well for mild infestations. Severe infestations will need a biological pesticide. This pesticide is made of Bacillus Thuringiensis, and is made for controlling mosquito larvae. 1 drop per gallon is all that is needed.
I use the Bacillus Thuringiensis drops two times per week when the infestation is really bad. I have found that a combination of the two may be needed in some severe cases.
Information from the manufacturer:
Specially Formulated for Decorative Water Gardens, Fountains & Areas Where Standing Water Exists
MICROBE-LIFT/BMC kills developing mosquitoes before they become breeding, biting adults, including those which may transmit West Nile Virus and Equine Encephalitis, and those which may transmit Heartworm Disease to dogs and cats.
MICROBE-LIFT/BMC is a liquid product, so it has no adverse effect on the aesthetics of ponds and water features
MICROBE-LIFT/BMC can be applied to areas that can contain aquatic life, fish and plants.
MICROBE-LIFT/BMC can be applied to areas used by or in contact with humans, animals, horses, livestock, pets, birds or wildlife.
One Teaspoon Treats 540 Sq. Ft. of Water in “Total Water Column”
Up to 14 days activity depending on application site
Disperses easily in water
No fish toxicity
No toxicity to non-target invertebrates
Significantly lower potential for development of resistance in target insect populations than chemical larvicides such as methoprene
No adverse aesthetics to the pond
No organic or inorganic residues
Rats love to eat weed. They will take off a branch per night easily. You will be left with a bunch of stems growing if rats can get to your plants. I have tried several deterrants such as: peppermint oil as a barrier, peppermint plants, mothballs, barriers of cinnamon and chili powder, and a few others.
Nothing worked. I live in an area with a lot of snakes, rats, coyotes, rabbits ,etc. The rats were eating lemons from my lemon tree, and stopped by my plants to munch on a branch of weed.
I finally found these rat traps on amazon. They are very easy to use, and I don't have to worry about setting the trap off while adding bait like the old style traps.
For bait, I have tried cheese, peanut butter, dried cranberries, and pecans. The traps with the dried cranberries caught a rat every night. After 2 weeks of traps with cranberries, no more rats came back until the next year!
Snails and slugs will leave slime all over the flowers, which is difficult to wash off. I have clipped buds off that were slime coated. They will also eat the leaves and the trim.
Whenever you see snails or slugs outside, place some Sluggo or some type of snail bait in areas concentrated with snails. The bait attracts snails when the bait gets wet.
I have tried placing bait close to the plants at first. It did kill the snails, but not before they slimed the plants. I now place the bait closer to an area more concentrated with snails, just not as close to my plants.
Anticipating rain with weather apps, and placing bait out more frequently during the spring rain will help keep the snails from eating your plants.