Yes, you can absolutely identify whether a Rubus cane will flower or remain vegetative by examining several key morphological features before any flowers appear. Here's how to distinguish between future flowering canes (floricanes) and purely vegetative shoots (primocanes):

Pre-Flowering Identification Features

Primocanes (First-year vegetative canes that won't flower this season):

• Thick, green, fleshy stems that remain succulent throughout the growing season
• Five leaflets per compound leaf - this is the most reliable diagnostic feature
• Longer internodes (spaces between leaves on the stem)
• Bright green, soft leaves early in the season
• Gradually tapering stems that get thinner toward the tips
• No flower buds visible even in late spring/early summer

Floricanes (Second-year canes that will flower and fruit):

• Woody, brown stems that have overwintered and hardened
• Three leaflets per compound leaf - the key identifier
• Shorter internodes with leaves closer together
• Smaller, darker colored leaves compared to primocanes
• Visible flower buds developing along lateral branches even before flowering
• Short lateral branches emerging from the main stem

Seasonal Timing Clues

Spring indicators: By late spring, floricanes should already show small green flower buds forming on short lateral branches, while primocanes will have none. Floricanes may also have developing fruit clusters by late May in temperate regions.

Leaf development: The leaflet number is your best early indicator - count the leaflets on compound leaves. Consistently seeing 5 leaflets means it's a primocane that won't flower this year, while 3 leaflets indicates a floricane that will produce flowers and fruit.

Why This Matters for Rubus pedunculosus

In your Kashmir specimens, the cane with fruits is clearly a floricane (second-year growth), while the purely vegetative shoots are likely primocanes that emerged this growing season. These primocanes will overwinter, become woody, and then flower and fruit next year as floricanes.

Practical tip: Look closely at the leaf structure on your vegetative shoots - if they consistently show trifoliate leaves (3 leaflets), they might actually be young floricanes that could still develop flower buds later in the season. If they show 5 leaflets, they're definitely primocanes that won't flower until next year