Winter Plant Care

Yes, the time for winter plant care is quickly approaching. Attending to certain tasks during our garden’s “off season”, can significantly ease the task load of the upcoming growing season. One of these important tasks is using Horticultural Oils for Dormant Spraying. Horticultural Oils effectively can eliminate overwintering pests such as scales and aphids along with fungal spores and eggs from other pests by essentially smothering them.

Application Guidelines

Horticultural Oil is most effective as a dormant spray when applied three times between November and February for our Mid-Tennessee temperate zone. For ease of remembering the timing, I like to use dates that we all typically keep in our heads anyway assuming they align, so here we go!

• First Spray: Apply right around Thanksgiving after 75% or more of the leaves have fallen OR after or first heavy frost if that comes before.

• Second Spray: This application should take place around Christmas when the trees are fully dormant and all leaves have dropped.

• Third Spray: This last application should occur around Valentine’s Day when you notice the first signs of buds swelling or green appearing on the emerging buds

You can apply more frequently on older material, but never more than once every 30 days.

Best Practices for Spraying

• Ensure the temperature will remain above 40 degrees for at least 24 hours post-application but remains below 70 degrees.

• Always apply either early in the morning or in the evening - not midday.

• Choose a calm and dry day to spray; avoid windy conditions and wet plant material.

• Thoroughly coat stems and branches to ensure all crevices are covered without dripping.

• Refrain from applying as a Dormant Oil within 30 days of using a sulfur based pesticide.

• Please remember to thoroughly clean your spray equipment after each use to prevent clogging. A small amount of oil can be used to help winterize equipment and keep things clean and rust free.

Keep in mind that these are all general practices and you should follow the instructions on the labels for concentration rates used for Dormant Spraying and plant compatibility as each brand may vary.

Frond Wishes for Happy Gardening!