top of page

Why Dormant Oil Spray Is a Must for Fruit Trees and Roses

Apr 1, 2025
2 min read

As the weather begins to warm and the garden slowly wakes from its winter slumber, there's a small but critical task that can make a big difference in the health of your fruit trees and roses: applying dormant oil spray


This early-season treatment is one of the easiest and most effective ways to prevent pests and diseases that commonly plague your trees and shrubs later in the year. But timing is everything — and your window to apply it is short. 


What Is Dormant Oil Spray? 


Dormant oil spray is an organic combination of horticultural oil (insecticide) and lime sulphur (fungicide). It’s designed to target overwintering insects, eggs, and fungal spores that have taken shelter in the bark and buds over the cold months. 


By applying it now, before buds open, you’re stopping those hidden threats in their tracks — before they can cause damage to your plant’s new growth, fruit, and flowers. 


Why Timing Matters 


Dormant oil spray must be applied before the buds leaf out. Once you start to see leaves or flowers emerging, it’s too late — applying the treatment at that stage can actually damage tender new growth. 


We typically recommend applying dormant spray sometime in late March or early April, depending on your the weather conditions. Keep an eye on your trees and the forecast to make sure you don’t miss your opportunity. 


How to Apply Dormant Oil Spray 


To get the best results, follow these guidelines: 

Wait for a dry day with no rain in the forecast 

✅ Apply when temperatures are above 5°C, ideally with 24–48 hours of above-zero weather before and after 

Spray in the morning so the product has time to dry during the day 

Mix only what you need — it’s best to apply a fresh batch each time 


Make sure to cover all branches and trunk surfaces thoroughly. This is where overwintering pests tend to hide! 


We’ve Got You Covered 


At Robert Plante Greenhouses, we carry Dormant Oil Spray Kits that include everything you need to get started. We also have a range of garden sprayers available if you need one for application. Our team is always here to answer questions and walk you through the process. 

84 Comments


bellefleur1988
4 days ago

For growers who keep running into the same problems, the Lvzhi Q&A pages gather questions and answers from across the growing process in one place.

Like

taixiumd5 gây chú ý nhờ việc đưa mã hóa MD5 vào quy trình xác minh kết quả Tài Xỉu. Từ góc độ người dùng, tôi đánh giá trải nghiệm này ở khả năng cung cấp thêm dữ liệu để kiểm tra thay vì chỉ dựa vào kết quả hiển thị. Người tham gia có thể ghi nhận chuỗi mã trước ván, sau đó đối chiếu khi ba viên xúc xắc được mở. Bên cạnh cơ chế này, giao diện được mô tả khá dễ sử dụng với các thao tác cơ bản được sắp xếp rõ ràng. Việc hỗ trợ trên thiết bị di động cũng giúp trải nghiệm linh hoạt hơn, nhất là khi chuyển đổi giữa máy tính và…

Like

https://top88.za.com/ khiến tôi chú ý đến cách khu vực bắn cá được chia theo nhà phát hành. Tôi thường chọn Fa Chai hoặc JDB trước, sau đó mới xem một trò cụ thể thay vì cuộn qua toàn bộ danh sách. Việc nhóm nội dung theo nguồn phát hành giúp tôi thu hẹp phạm vi tìm kiếm ngay từ đầu. Tôi đánh giá cách tổ chức này phù hợp với người đã có vài lựa chọn quen. Khi các nhóm đã thành mốc nhớ, việc quay lại đúng nhà phát hành, đổi trò và tiếp tục phiên diễn ra nhanh hơn, ít phải dò toàn bộ kho game quen hơn

Like

Ondra
Aug 27

I never realized how short the application window was until I missed it one spring and paid the price with scale on my apple trees. The point about targeting overwintering eggs in the bark makes so much sense now. By the way, I keep a supplier of construction wire, tie wire, rebar supports, anchor bolts and temporary fencing for importers and distributors I like to share: https://www.leeter.cn/products/anchors-stakes-bolts/

Like

Perm State Medical University in Russia is an interesting option to explore for students considering medical education abroad. I’d suggest looking beyond tuition fees and checking factors such as the university’s curriculum, clinical exposure, teaching language, recognition, student support, and living conditions before making a decision.


Like
Robert Plante Greenhouses Logo.

Proudly serving Ottawa, Robert Plante Greenhouses is Ottawa's Premier Garden Centre. We offer a diverse range of products, including annuals, perennials, tropicals, houseplants, succulents, cacti, shrubs, trees, garden tools, ornaments, soil, supplies, and more. Visit us to explore our extensive selection for all your gardening needs!

 

COME VISIT US TODAY!

CONTACT INFO

 

ADDRESS

4228 NAVAN RD.

NAVAN, ON

K4B 1H9

 

GENERAL INQUIRIES

(613) 835-9266

info@robertplantegreenhouses.com

PRESS INQUIRIES

Colin Matassa

colin@robertplantegreenhouses.com

HOURS OF OPERATION

REGULAR HOURS:

9:00 - 5:00    MONDAY

9:00 - 5:00    TUESDAY

9:00 - 5:00    WEDNESDAY

9:00 - 5:00    THURSDAY

9:00 - 5:00    FRIDAY

9:00 - 4:00    SATURDAY

9:00 - 4:00    SUNDAY

Robert Plante Greenhouses voted as Best Plant Nursery in Ottawa.

© 2024 Les Serres Robert Plante Greenhouses

bottom of page