How to Pick Plums: Ripeness, Technique & Storage

How to tell if a plum is ripe

Plum varieties range from deep purple-black to red to yellow-green, so color is only useful once you know what the variety looks like at peak. Focus on these cues instead:

• The bloom:Like blueberries, ripe plums develop a dusty, powdery white-blue bloom on their skin. It's natural wax the fruit produces — a sign of freshness and full development. A shiny plum with no bloom is either underripe or has been handled too much.
• Give at the shoulder: Press gently near the stem end. A ripe plum yields slightly — not soft like a very ripe peach, but definitely not rock-hard. The cheeks should give a little too.
• Ease of release: A ripe plum twists off the branch cleanly with a gentle upward roll. Resistance means it needs more time.
• Background color: For red and purple varieties, the skin should be deep and fully saturated with no green patches. For yellow varieties like Shiro, look for fully golden skin, no green remaining.

The Santa Rosa plum — developed by Luther Burbank and still grown at several Brentwood and Morgan Hill farms — is tart at the skin and sweet near the pit, with a complex flavor unlike grocery-store plums. It's ripe when the skin is deep crimson and the flesh just starts to give near the stem. Early June through early July in California.

Picking technique

Same twist-and-lift as peaches and nectarines: cup from below, roll gently upward. Plums bruise more easily than they look — their flesh is dense but the skin splits under sharp pressure.

• Keep the bloom intact: Rubbing or squeezing plums removes the bloom and exposes the skin to moisture and bacteria. Handle as little as possible.
• Don't drop: A plum dropped into a bucket will split or bruise internally. Lower gently.
• Cluster check: Plums often grow in clusters of 2–4. Check the whole cluster — the most sheltered one at the back is often the ripest.

Variety quick guide

• Santa Rosa: Red-purple skin, golden-amber flesh near pit. Tart skin, sweet flesh, intensely aromatic. Classic California plum. June–July.
• Elephant Heart: Large, dark red, heart-shaped. Blood-red flesh. Very sweet and juicy at peak. Mid-to-late season.
• Shiro: Yellow-green skin turning golden. Mild, honey-sweet. Early season (June).
• Italian Prune (Fellenberg): Blue-purple, oval. Drier, denser flesh — excellent for baking and drying. Late season (August–September).

Storage after picking

• Firm-ripe:Leave at room temperature for 1–2 days to soften, then refrigerate. Don't refrigerate hard plums — cold stops ripening and makes them mealy.
• Soft-ripe: Refrigerate immediately and use within 3–5 days.
• Freezing: Halve and pit, freeze in a single layer on a baking sheet, then bag. Excellent for jam, galettes, and sauce. Keeps 6–12 months.

What to bring

• Shallow containers — plums stack okay but not more than 3–4 layers deep
• A cooler for the drive home on hot days
• Clothes you don't mind staining — plum juice runs deep purple