Santa Rosa Plum

Luther Burbank's masterpiece Japanese plum, producing medium-large fruits with crimson skin, amber flesh tinged with red, and a rich, tangy-sweet flavor. Santa Rosa is partially self-fertile but produces better crops with a pollinizer like Beauty or Satsuma plum nearby. One of the most widely planted plum varieties worldwide.

Santa Rosa plum pits require cold stratification of 90-120 days in moist sand at 33-40°F. Crack the hard shell carefully or scarify before stratifying. Sow one inch deep in spring. Seedlings will not be true to Santa Rosa type, as Japanese plums are highly variable from seed. For true-to-type trees, graft Santa Rosa scion wood onto Myrobalan, Citation, or Marianna 2624 rootstock using whip-and-tongue grafting in late winter.

The Season Plate

Your Santa Rosa Plum Year

Composed for Zone 7 · typical seasons · frost passes Apr 2, returns Nov 1

Sow Santa Rosa Plum Feb – Mar, pick Jun – Jul. Set your climate below and every date on this plate re-times itself.

Sowing window

Feb – Mar

re-timed to your frost dates

Plant out

after Apr 2

once frost risk has passed

First picking

around Feb 14

≈ 1095 days from sowing · 50-100 lbs per plant

Composed for —ColdTemperateMildWarmUse my locationUsed once to set your season · only the zone is kept

Week-by-week Santa Rosa Plum reminders watering, feeding and pruning, timed to your dates

In the app

Frost alerts for your garden a warning before a cold night costs you the crop

In the app

Succession sowing dates so the picking never gaps mid-season

In the app

Keep my dates — free for 7 daysWe nudge you as each window opens · cancel anytime

Santa Rosa plum trees thrive in full sun with well-drained soil at pH 6.0-6.5. Plant bare-root trees in late winter, spacing standard trees 18-22 feet apart or 10-12 feet on semi-dwarf rootstock. While partially self-fertile, planting a Japanese plum pollinizer like Beauty, Satsuma, or Burgundy within 50 feet significantly increases fruit set and yield.

Water deeply every 7-10 days during the growing season. Thin fruit to 4-6 inches apart when marble-sized to improve size and prevent limb breakage from heavy crops. Santa Rosa requires about 400 chill hours, making it adaptable to mild winter areas. Train to an open vase shape with well-spaced scaffold branches to allow light into the canopy center.

Prune moderately in late winter, removing about 20% of the previous year's growth. Japanese plums fruit on one-year-old wood and on spurs, so avoid removing all new growth. Apply balanced fertilizer in early spring before bloom. Protect from late frost in marginal zones, and monitor for brown rot during wet springs with preventive fungicide applications.

Plant garlic and onion family members nearby to deter aphids and plum borers. Marigolds attract beneficial insects and repel nematodes. Comfrey at the drip line accumulates minerals and provides nutrient-rich mulch. Tansy attracts parasitic wasps that control plum pests. Avoid proximity to walnuts due to juglone toxicity. White clover between rows fixes nitrogen and supports pollinators.

The Society Table

Garlic belongs beside it. Walnut Tree doesn't.

Old growers' knowledge, checked against Santa Rosa Plum's real companion table below — test any plant you're growing.

Grows well in the company of · 2

GarlicMarigold

Keep apart · 1

Walnut Tree

Plant Santa Rosa Plum with good neighboursThe planner flags conflicts before they're in the ground

Santa Rosa prefers well-drained loamy soil with pH 6.0-6.5. Tolerates slightly heavier soils than peaches but still suffers in waterlogged conditions. Apply a balanced 10-10-10 fertilizer in early spring at one pound per inch of trunk diameter. Avoid excessive nitrogen, which promotes vegetative growth over fruiting. Supplement with potassium for fruit color and quality. Mulch with 3-4 inches of organic material, keeping it away from the trunk.

Ideal Temperature

Hardiness Zone Compatibility

Santa Rosa plums ripen in late June to early July, developing deep crimson-purple skin with a slight bloom. Harvest when fruit yields to gentle pressure and the amber flesh near the skin turns reddish. Fruits do not ripen well off the tree, so pick at near-full maturity. Twist gently to detach with the stem. A mature tree can produce 75-100 pounds of fruit annually. Harvest over 2-3 weeks as fruit ripens unevenly.

Storage & Preservation

Fresh Santa Rosa plums keep 3-5 days at room temperature or up to 3 weeks refrigerated at 31-32°F. Their tangy-sweet flavor makes outstanding plum jam, preserves, and chutney. Excellent for canning in light syrup and for drying into prune-like treats. The rich color produces beautiful plum wine, plum sauce for Asian cuisine, and plum butter. Freeze halved and pitted for year-round use in baking.

Troubleshooting Common Problems

Overcropping is the most common issue with Santa Rosa, as the tree sets fruit prolifically without adequate thinning, leading to small fruit and broken limbs. Brown rot can devastate crops in humid climates. Black knot is a persistent fungal disease in some regions. Bird damage to ripening fruit requires netting. Gophers and voles can damage roots, especially on young trees in rural settings.

Growing Tips

1. Plant Santa Rosa in the sunniest position available, ideally receiving at least 8 hours of direct sun per day. Full sun exposure is directly linked to fruit sweetness and colour development, and insufficient light is one of the most common reasons for poor flavour and productivity in home orchards.
2. Select semi-dwarf rootstock such as Myrobalan 29C or Citation for most home gardens. These keep the tree at a manageable 3.5-4.5 metres, making netting, pruning, and harvesting practical without a ladder, while still supporting generous yields.
3. Improve pollination by planting a compatible Japanese plum variety within 15 metres. Although Santa Rosa is partially self-fertile, planting alongside Burgundy, Beauty, Laroda, or Late Santa Rosa consistently produces heavier and more uniform fruit set.
4. Thin fruit aggressively after the natural drop, spacing plums 8-10 cm apart along every branch. This feels drastic but is essential: unthinned Santa Rosa trees produce masses of small, watery, poorly coloured fruit, while properly thinned trees yield large, richly flavoured, market-quality plums.
5. Water deeply and consistently from fruit set through to harvest using drip irrigation. Avoid frequent shallow watering, which encourages surface rooting and leaves trees vulnerable to drought stress. Inconsistent moisture during the final four weeks before harvest is the primary cause of fruit splitting and cracking.
6. Prune Santa Rosa in late summer, after harvest, to shape the canopy and improve light penetration for next year. Japanese plums should be pruned more frequently than European varieties to control their vigorous growth habit. Aim to maintain an open vase or modified central leader form that allows sunlight to reach all parts of the canopy.
7. Feed with a balanced fertiliser (10-10-10 or similar) in early spring just as buds break, followed by a low-nitrogen potassium-rich fertiliser in early summer when fruit is sizing up. Avoid heavy nitrogen applications in summer, which push soft, disease-prone vegetative growth at the expense of fruit quality.
8. Protect developing and ripening fruit from birds and squirrels by draping bird netting over the entire tree canopy. Begin netting when fruit starts to colour up, typically 3-4 weeks before expected harvest, as damage from wildlife can be rapid and extensive once fruit is visible.
9. Apply a 7-10 cm layer of wood chip or straw mulch across the entire root zone out to the drip line each spring. Mulch conserves moisture, moderates soil temperature, suppresses competing weeds, and gradually feeds the soil as it breaks down. Always keep mulch at least 15 cm away from the trunk to prevent collar rot.
10. Monitor for brown rot starting from the moment fruit begins to colour. Remove any fruit showing brown discolouration, fungal sporulation, or cracks immediately and discard away from the garden. A single affected fruit left on the tree or ground can spread the disease to dozens of neighbours within days during warm, humid weather.