Rosemary Bonsai Care TipsGeneral Information: Rosemary is an evergreen plant with narrow, aromatic dark green leaves that are the source of the herb Rosemary. It will bear small clusters of light lavender blue flowers in spring and occasionally during the summer. Rosemary grows quite rapidly, providing shoots that can be clipped and used for seasoning.
Lighting & Placement: Unwrap your Rosemary Bonsai upon receipt and water if the soil is dry to the touch. Place the plant on a sunny windowsill or another location where it will receive two to four hours of morning or late afternoon sunlight each day. Rosemary will thrive indoors in a room with temperatures of 50° to 70°F and high humidity. Do not place the plant near heat sources, such as stoves or heaters.
It is beneficial to move your Bonsai outside to a lightly shaded spot after the danger of frost has passed. The soil will dry out more quickly outdoors so pay close attention to watering requirements. The Bonsai will need to be brought indoors each winter before temperatures drop below freezing.
During winter months indoors, your Rosemary will do best in a draft-free, bright, cool, humid room with night temperatures of 40° to 55°F and daytime temperatures below 60°F. Extra humidity may be provided either by frequent misting or by setting the plant in a decorative tray filled with pebbles and water added to a level just below the bottom of the pot.
Watering: Your Rosemary Bonsai requires frequent watering. You should plan to water it every two to three days. Never allow the soil to dry out completely. Usually you can tell when it needs watering by the color and feel of the soil surface. The soil color lightens as it dries and the surface feels dry to the touch when it needs watering. After watering, when the soil surface is moist, the soil color is a deep chocolate brown.
To water, place the plant in a pan with 1” to 2” of water and soak for an hour or so until the soil looks and feels moist. If you are unable to water it for several days, you can enclose the pot in a plastic bag (the way we shipped it to you) immediately after watering. The bag acts as a greenhouse and will keep the soil moist for at least a week.
In some regions salts and minerals will build up on the surface, discolouring the soil. Either spray the soil surface with water, or submerge the entire pot in water for 10 minutes to flush out the accumulated salts.
Pests & Diseases: Rosemary is susceptible to powdery mildew fungus which appears on the young growth as a powdery white substance, usually when it is not receiving adequate light. Spray once a month or as needed with a sulphur based fungicide such as Safer brand Garden Fungicide.
The sulphur spray will also help control spider mites. If aphids or other insects appear, spray with a non-toxic insecticidal soap. Follow the directions on the label. Do not use toxic pesticides.
Fertilizing: The plant should be fertilized every six weeks between spring and mid-summer, using regular houseplant food at half strength.
Pruning: Pinch back new tips as necessary to retain the plant’s shape and keep it compact and bushy. Completely remove any branch that dries out and dies. This may occasionally occur due to some stress the plant experiences and is not uncommon for Rosemary. After a thorough washing, the healthy trimmings may be dried and the leaves used for seasoning.
Root Pruning/Repotting: Every spring your Bonsai will need its roots pruned. Gently remove the plant from the pot; carefully remove some of the soil around the sides and bottom of the root ball. Cut off one-fourth of the roots all the way around and up from the bottom. Place fresh, porous soil in the pot (a houseplant soil mix is suitable) and replant the Bonsai. After potting, mist the plant with water and soak it in a solution of water and Superthrive or other Vitamin B-1 transplant shock-reducing treatment.
Toxicity: Plant material in general often contains toxins and should not be eaten.
More Bonsai Trees & Plants
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