Latham Raspberry

Latham was introduced by the University of Minnesota in 1920 from a King × Loudon cross, part of an early fruit breeding initiative that would eventually release over a hundred new cultivars. By the 1930s and 1940s it had become the most widely planted red raspberry in the United States, a commercial dominance that lasted for decades and established it as the standard against which subsequent Midwestern cultivars were judged. Its longevity reflects the breeding objective it was built to meet: combining the cold-acclimation genetics necessary for Zone 3 winters with large-berry tendency, vigor, and tolerance of marginal soils. Over a century after its release, Latham remains in active production, a rarity among cultivars of its era and a measure of the durability of the Minnesota program’s early work.

Consistent moisture during cane development and fruit set is the primary cultural lever for Latham. In humid summer climates, that moisture also elevates disease pressure, so adequate row spacing and trellis support — which lift canes off the ground and open the canopy — do double duty. Aim for a soil pH between 5.5 and 6.5; above 6.8 the plant struggles to access iron and manganese, and yellowing between leaf veins follows quickly. Incorporate compost or aged wood chips along the drip zone annually rather than digging around the crown, since the fibrous root system stays close to the surface. Latham tolerates partial shade better than most summer-bearing reds, a useful characteristic where afternoon heat in zones 6-8 can burn fruit on exposed canes. Rows oriented north-south improve light penetration when cane density increases after the first two seasons.

USDA Hardiness Zone: 3-8
AHS Heat Zone: 1-6
Chill Hours: 800-1000
Sun Requirements: Full Sun to Partial Shade
Soil pH: 5.5-6.5
Soil Type: Loam, well-drained with high organic matter
Soil Drainage: Well-drained
Water Requirements: Medium (1-1.5 inches per week during growing season)
Plant Spacing: 2-3 ft apart in rows, rows 6-8 ft apart
How to Prune: Cut floricanes to ground after fruiting; in spring, top primocanes at 12 inches above trellis wire; thin to 4-5 strong canes per foot of row

Latham produces upright, thorned biennial canes that typically reach 4 to 6 feet tall with a colony spread of 2 to 4 feet, expanding year over year via underground runners. The biennial cane structure — primocanes growing vegetatively in year one, fruiting as floricanes in year two — means the planting always contains two age classes at once, which contributes to the densely textured appearance of an established row. Thorns are present but moderate compared to older selections; gloves remain practical during harvest and pruning. Fall foliage turns burgundy to red before drop, providing seasonal color beyond the fruiting period. The suckering root pattern creates a living hedge effect over time, useful for erosion control on gentle slopes and as a visual screen along field edges. Structural pruning each autumn — removing spent floricanes entirely and thinning primocanes to four or five per foot of row — keeps the planting productive and reduces fungal disease habitat.

Mature Height: 4-6 ft tall
Mature Spread: 2-4 ft wide
Growth Habit: Upright, suckering shrub with thorny biennial canes
Growth Rate: Fast
Foliage Type: Deciduous
Food Forest Layer: Shrub
Leaf Color: Green
Fall Foliage Color: Burgundy/Red
Thorns?: Yes
Attracts Wildlife: Bees, butterflies, birds, small mammals
Life Span: Perennial (canes biennial, crown perennial)

Latham is self-fertile, carrying its own compatible pollen, so a single plant or row will set fruit reliably. Bloom runs from late April through late May in a temperate climate, with white five-petaled flowers that open sequentially along the cane rather than all at once. This staggered bloom extends the window for bee activity and provides some insurance against late frost taking the entire crop. Because the variety is insect-pollinated primarily through bees, fruit set improves noticeably in gardens with active pollinator populations. Planting companion herbs such as yarrow or echinacea nearby — noted in the variety's companion plant list — maintains bee traffic through the raspberry bloom window without requiring a second raspberry cultivar. Where cross-pollination is desired to increase yields further, any summer-bearing red raspberry with overlapping bloom makes a compatible partner.

Bloom Season: Very Early
Bloom Window: Late Apr - Late May
Pollination Requirements: Self-fertile
Pollination Mechanism: Insect-pollinated (bees); self-fertile
Flower Color: White

Measuring 0.75 to 1 inch in diameter — medium-large for a heritage floricane type — berries present bright red skin and firm flesh that holds together during picking and short-term storage. Flavor runs sweet with moderate acidity and the concentrated raspberry aroma characteristic of older cultivars; Brix values in well-managed plantings typically fall in the mid-to-upper single digits. Fruit color is uniform at harvest with minimal green shoulder, which matters for fresh-market presentation. Shelf life is brief: two to three days refrigerated before quality declines, so Latham has historically excelled as a processing variety. Freezing, canning, preserves, and baking are traditional uses where the berry's firm texture holds up well after thawing without the mushiness common in softer cultivars. The floricane-bearing habit concentrates the entire crop into roughly three to four weeks in early to late July in a temperate climate, favoring growers who want to harvest in volume for batch preservation rather than pick repeatedly over a longer season.

Ripening Season: Early
Harvest Window: Early Jul - Late Jul
Fruit Size: 0.75-1 inch
Flavor: Sweet; suitable for fresh eating, canning, freezing, and baking
Fruit Color: Bright red
Fruit Texture: Firm
Bearing Habit: Floricane (summer-bearing); single crop on second-year canes
Years to Bear: 1-2 years after planting
Storage Life: 2-3 days fresh refrigerated; excellent for freezing, canning, and preserves
Culinary Uses: Fresh eating, jams and preserves, baking (pies, desserts), syrups, freezing, canning

Latham shows the strongest pathogen resistance in its profile against Phytophthora root and crown rot (Phytophthora spp.), where it performs at a resistant level — a meaningful advantage in heavy clay or poorly draining soils where this pathogen is most damaging. Cane blight (Leptosphaeria coniothyrium), spur blight (Didymella applanata), and anthracnose (Elsinoe veneta) all encounter moderate resistance, reducing — but not eliminating — the need for intervention in humid climates. Gray mold (Botrytis cinerea) is the primary weak point, with moderate susceptibility that worsens whenever canopy airflow is restricted. Cultural management is the first line of defense: thin primocanes aggressively in spring, remove and destroy spent floricanes immediately after harvest, and avoid overhead irrigation during fruit ripening. OMRI-listed copper-based sprays applied at early blossom can reduce spore loads. Spotted wing drosophila (Drosophila suzukii), raspberry crown borer (Pennisetia marginata), raspberry fruitworm (Byturus unicolor), and several aphid species (Amphorophora agathonica) show moderate susceptibility. Monitor for SWD starting at first color break using apple cider vinegar traps; exclude with row cover (0.8 mm mesh or finer) during the final ripening window. Control crown borer larvae by removing wilted cane tips in midsummer. Kaolin clay or OMRI-listed spinosad applications address fruitworm pressure where monitoring shows threshold populations.

Gray Mold / Botrytis Fruit Rot: Moderately Susceptible
Phytophthora Root and Crown Rot: Resistant
Cane Blight: Moderately Resistant
Spur Blight: Moderately Resistant
Anthracnose: Moderately Resistant
Spotted Wing Drosophila: Moderately Susceptible
Raspberry Crown Borer: Moderately Susceptible
Raspberry Fruitworm: Moderately Susceptible
Aphids: Moderately Susceptible

• Remove Floricanes Promptly: Cut spent second-year canes to the ground immediately after harvest rather than waiting until fall. Decomposing cane tissue is a primary reservoir for Botrytis overwintering inoculum, so early removal directly reduces gray mold pressure the following season.
• Thin Primocanes Hard: Four to five canes per foot of row sounds sparse but is the right density. Overcrowded canes reduce fruit size, block airflow, and create the humid microclimate Botrytis and cane blight need to establish.
• Check Drainage Before Planting: Dig a hole 12 inches deep and fill with water; if it does not drain in an hour, amend with coarse compost or raise the row before establishing the planting.
• Support Canes at Two Heights: A two-wire trellis — one wire at 3 feet and one at 5 feet — keeps canes upright and maintains the airflow that counters fungal disease. Unsupported canes arch and create shaded, damp contact points with the soil.

Our 365-Day Plant Guarantee: We ensure that our plants are delivered to you alive and healthy. If your plant does not survive its first year, you're eligible for store credit under these conditions:

1. Your location falls within the appropriate USDA hardiness zone for the plant variety (refer to our hardiness zone map).
2. You maintain the roots' moisture and plant within three days of delivery, following the instructions in our Planting Guide.

If you're concerned about your plant's health, please consult our guide, How to Tell if Your Tree is Dead or Dormant. Remember, our plants are shipped in a dormant state and may leaf out at different times based on their species. To check for plant vital