Rose Growing Guide: Planting, Care & Harvest

Rosa spp.

Growing calendar

Typical timing for central Japan (Kanto region). Shift it for your own climate, and record your actual dates.

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GrowingFlowering

Guides

Common problems

Start from what you can see on the plant.

Yellow leaves Leaves dying White powder Leaf spots Pests Fruit problems

Pests and diseases (12)

Problems recorded for this plant, most serious first.

Powdery Mildew

MajorDisease

White patches appear scattered on the upper leaf surface at first, then the whole leaf is coated in a white powder. Leaves later yellow, brown and die back, and reduced photosynthesis cuts growth and yield.

Black Spot

MajorDisease

On roses, dark brown lesions with radiating edges form on the leaves, which yellow around them and drop. On pear, sooty black lesions appear on leaves, fruit and the calyx of young fruit, deforming the fruit.

Crown Gall

MajorDisease

Irregular galls form at the crown and on the roots, gradually enlarging and turning woody. They block the flow of water and nutrients, so the plant loses vigor and may die.

Sawflies

MajorPest

Feeding advances rapidly from the leaf margin, leaving only the veins within a short time. The larvae rear up when disturbed and are often lined up on the leaf underside.

Root Bound

CommonDisorder

Leaves wilt even right after watering and roots push out of the drainage holes. Water runs off the surface instead of soaking in, foliage pales and growth stops.

Spider Mites

CommonPest

Fine white stippling spreads across the upper leaf surface, and the leaf eventually whitens and dies back. In heavy infestations fine webbing appears on leaf undersides and shoot tips.

Scale Insects

OccasionalPest

Small white or brown shell-like insects dot the shoots and leaves. The plant loses vigor and honeydew-fed sooty mold blackens the shoots and foliage.

Longhorn Beetles

OccasionalPest

Sawdust-like frass is pushed out at the trunk base or branch crotches. The wood is hollowed out, the tree loses vigor, and the trunk may snap in strong wind.

Scarab Grubs

OccasionalPest

The plant wilts despite watering and growth halts abruptly. Lift the plant and there are almost no roots; dig into the soil and white C-shaped grubs appear.

Rust

OccasionalDisease

Small raised orange-yellow to red-brown pustules form on both leaf surfaces, then rupture and release powdery spores. Heavy infection yellows the leaves and kills them early.

Sooty Mold

OccasionalDisease

A thin black sooty mold spreads over the upper leaf surface, shoots and fruit. It does not invade the tissue itself, but it blocks photosynthesis and badly spoils appearance.

Leafrollers

OccasionalPest

Leaves are webbed into tubes or folded in half, with a green or brown caterpillar inside. Shoot tips and fruit surfaces are also gnawed, disrupting growth.

Written byYasuGrowing vegetables and fruit in Chiba, Japan, and building Gadenin. Corrections are welcome. 15 years of growing.