Aphids attacking my bridal wreath bushes

(Question)

Hi,
Our backyard is backing on to green belt and back of the fence we have bridal wreath bushes all along approximately 45 ft wide and spring will be very beautiful!! with whole fence bloomed with flowers. This yr after our flowers dried up and with the new buds I see aphids on them and noticed bit early as they just started I’m spraying soap water and spraying with my hose as it is very bushy and too wide I ‘m scared it might spread very fast. Please let me know how can I get rid of them on my plants as it is spread wide on my back fence. I’m attaching pic of aphids all over spreading on new buds. Please do advice I do not want to loose my blooms for next spring. Thank you.

(Answer)

Thank you for contacting the Toronto Master Gardeners concerning your bridal wreath Spirea (Spiraea prunifolia).

What a beautiful sight to see it in full bloom in the spring and how frustrating just when the new young leaves are ready to emerge they are attacked by aphids just waiting to suck out the juices from the tender new growth. Unfortunately, your picture was not attached to your response.

There is a wealth of information on our website on  how to control these pests. Simply type aphids in the Find It Here box located on the right side of the page: Aphids

The following information is from a few of our archived posts:

There are over 300 species of aphids that live in the Ontario area. They come in a wide variety of colours ranging in black, brown, grey, green, white, red, and yellow. Young aphids or nymphs also look different than adult aphids. The youth are more transparent and the adults are darker in colour with more pronounced antennae and legs. Its possible that if it looks like an aphid and has one of these colours and aphid attributes it is an aphid. Aphids reproduce rapidly and can grow to have large populations and decimate large amounts of plant material in a short time.

To control aphids before they cause damage you can create a habitat friendly to predatory species that prey on aphids such as lacewings, predatory wasps, and ladybugs to eat them. To promote beneficial insect habitat it is recommended that you provide nectar producing plants in the garden, provide a drinking or watering hole, and provide a shady place for them to hide during heat spells. It is not recommended to  use insecticides indiscriminately as that can reduce predatory insect populations in the long run and cause the aphid populations to grow larger as a result. We need long term and nonchemical solutions for these problems while promoting pollinators as well.

The  best solution to ridding your plants of these pests is your garden hose set on full blast. Spraying them will knock them to the ground and they will be unable to return to the host. Do this every few days until you no longer see any signs of them. Where aphid infestation is abundant you can use insecticidal soap, which is available at your local garden center. Make sure to follow directions on the label.

The following website give additional information on how to control these pests: Aphids

Although aphids are generally considered not to cause lasting damage to trees or shrubs, repeated severe infestations could weaken your shrubs over time, so it is important to give your shrubs their best chance against insect pests by making sure that they are and healthy well watered during dry spells and mulched around their bases. Mulch not only retains moisture and regulates soil temperature it also has the added benefit of suppressing weeds. This means less work and more enjoyment of your garden.

Good Luck!

June 11, 2021