Growing Raspberries in Southern Wisconsin Lisa Johnson, Dane County UWEX
Raspberry Raspberry Plant Anatomy Cultivar Selection Site Selection, Planting Fertilizer application Cane Support Systems Pruning Mulch and Winter Protection Major Diseases and Insects Further Resources
Raspberry Plant Anatomy Woody perennial Crown Roots Canes: Primocanes& floricanes Primocanes:first year non-fruiting canes on summer-bearing cultivars OR fruiting canes on fall-bearing cultivars Floricanes: Second year fruiting canes on summer-bearing cultivars) Leaves Flowers (borne in clusters on lateral stems) Plants are most productive for 8-10 years
Tips Floricanes Side Branches Primocanes Crown Roots Crown Buds Raspberry Plant Anatomy
Immature Buds 70% 20% 6% 4% Fruit buds Leader Bud Roots Raspberry Plant Anatomy
Stigma Style Anther Filament Ovule Receptacle Raspberry Flower Structure
Raspberry Flowers and Fruit Flowers are borne at the end of lateral shoots Flowers are self fruitful, bees do 80-90% of pollinating Aggregate Fruits poor pollination affects fruit quality greatly. If each carpel is not pollinated, it doesn t fill out
Summer-bearing Raspberry Fruiting Habits Produce fruit on two year old canes (floricanes) Canes must be winter hardy in order to fruit the next year (hardiness is important in cultivar selection!) Need short days, cool temperatures to initiate flowers Produce one crop in summer; floricane dies after fruiting (can remove canes after bearing) If using heading back cuts to control height, don t remove more than 25% of cane New canes sprout from underground root buds ( leader buds) Planting can spread over time due to rhizomatic roots
Recommended Summer-bearing Cultivars Cultivar Cultivar Hardiness Harvest Season Productivity Fruit Size Attractiveness Firmness Flavor Freezing Quality Boyne Very Early Very Medium Fair Fair Good Very Nova Good Early Very Medium -large Very Good Very Prelude Fair Early Good Medium Good Good Very Latham Excellent Mid Very Medium -large Kilarney Excellent Mid Very Medium -large Very Good Very Good Good Very Excellent Good Very Haida Good Late Very Medium Excellent Excellent Very Good Very Source: University of Minnesota http://www.extension.umn.edu/distribution/horticulture/dg1108.html
Fall-bearing Raspberry Fruiting Habits Fruit borne on one-year-old (current) canes (primocanes) Day length, temperature don t affect flower initiation Initiate flowers June-July; produce flowers early July-Aug. Fruits produced late August/September to frost Fruiting zone (where fruits are produced) starts at tip of the flower cluster and moves from top of cane down Hardiness not an issue: canes don t have to overwinter Pruning is easier (don t have to thin twice, only once) More problems with spotted wing drosophila than summer-bearing raspberries (so far!)
Recommended Fall-bearing Cultivars Cultivar Cultivar Hardiness Harvest Season Productivity Fruit Size Attractiveness Firmness Flavor Freezing Quality Autumn Bliss Fair Early Very Large Very Fair Very Very Polana Good Early Excellent Medium Very Fair Fair Good Autumn Britten Fair Early Very Large Very Very Josephine Fair Mid Excellent Large Very Very Caroline Fair Late Fair Large Very Very Heritage Very Late Fair Medium Very Very Excellent --------- Very Very Very --------- --------- Good Source: University of Minnesota http://www.extension.umn.edu/distribution/horticulture/dg1108.html
Raspberry Site Selection Good air circulation but protected site from wind Reduces leaf damage and dries faster after rain If possible, plant on a slight slope for cold air drainage Summer bearing- north facing slope Fall bearing- south facing slope Well drained mineral soil (not muck or heavy clay) Ideal: deep sandy loam with 5-7% organic matter and a ph of 6.0-6.8 (optimal), can tolerate 5.5-7.5 Avoid siting your raspberries where potatoes, peppers, tomatoes, eggplant, other caneberries, or strawberries have grown within the past 3 years.
Planting Raspberries Plant in the spring after danger of frost is passed Plant at same depth as in nursery at old soil line or so leader buds are 1-2 under ground Make sure roots are spreading, not spiraling Water right after planting If using row planting, plant rows 18 wide, with 2 feet between plants and 8 between rows
Fertility Established plants: 4 to 5 pounds of 10-10-10 fertilizer for each 100 feet of row. Apply half in early May and half in early June If your soil test indicates high phosphorus and potassium levels, use 1½ to 2 lbsurea per 100 feet of row instead(same timing). DO NOT overfertilize with nitrogen; plants may become more susceptible to fungal diseases Do not fertilize after August 1; Late spring or summer fertilization encourages succulent, late season growth which is susceptible to winter damage. New plantings:divide the total amount for the season into thirds, and apply the first third 2 weeks after planting, the next third 1 month later, and the final third an additional month later. Manure may be used as an organic alternative. fertilizers. Apply 50 to 100 pounds of wellrotted barnyard manure (cow or horse) per 100 feet of row and work lightly into soil
Raspberry Trellising Systems Row system: for narrow rows only Plants 2-3 feet apart in rows Rows 6-10 feet apart
Raspberry Trellising Systems T-stake system for wider rows
Raspberry Trellising Systems V-Supports
Pruning: Cutting Edge Humor Moral of the story: use sharp pruners
Pruning Summer-bearing Raspberries Two times Late summer after bearing Remove finished floricanes by cutting down to ground level (they will not fruit again) Thin out new shoots to 4-6 canes per foot of row Dormant Season Head back primocanes by 25% Cut back side branches slightly (no more than 25%) Remove weak, diseased or damaged wood Thin primocanes to 4-6 per foot of row
Heading Back Summer-bearing Raspberries Take no more than 25% off the tips Encourages more branching
Pruning Fall-bearing Raspberries Once (unless pruning for a small summer crop as well as a larger one in fall) Dormant(late fall or early spring) Cut back all canes to the ground Can use a mower if blades are sharp enough to make clean cuts Can use floating row cover in spring to hold in heat and start harvesting 5-15 days earlier. Remove covers when temps reach 80ºF or canes reach 12-18 in height (whichever comes first) Thin canes to 4-6 per foot of row once they are 6 tall or so
Thinning Canes (both Summer & Fall-bearing BEFORE AFTER Thin to 4-6 canes per foot of row
BEFORE
AFTER
Mulching and Winter Protection Using mulch is desirable for: Retaining moisture Protecting roots Reducing weeds Shredded bark mulch, straw May need to use a little more nitrogen fertilizer as a result Winter Protection From rabbits! Chicken wire or hardware cloth (ideally 36 )
Raspberry Diseases Pruning cuts Root and crown rots (Soil borne. Occurs where soil is too heavy and drainage is poor, or due to poor pruning practices)
Raspberry Diseases Cane Blight (fungal, usually enters through wounds) Spur Blight (fungal, usually enters through leaves and then to canes)
Raspberry Diseases Anthracnose (fungal, can attack leaves and stems, hard to control no fungicides effective)
Raspberry Insect Pests Japanese Beetles Hand pick in evening or early morning Don t use Japanese beetle traps No silver bullet
Raspberry Insect Pests Spotted Wing Drosophila
Raspberry Cane Borer Raspberry Insect Pests
Resources UWEX Learning Store (http://learningstore.uwex.edu/) Growing Raspberries in Wisconsin A1610 Midwest Fruit Pest Management Guide A4104 Raspberry Pest Management for Home Gardeners A2128 Plant Disease Diagnostic Clinic Website (http://labs.russell.wisc.edu/pddc/) Cane Blight XHT1242 Raspberry Anthracnose XHT1232 Root and Crown Rots in the Garden XHT1072 Spotted Wing Drosophila XHT1237 Japanese Beetle XHT1062
Thank You! For a copy of this presentation, or to ask a horticulture question, call or email Lisa Johnson Dane County UWEX Horticulture Educator 608-224-3715 Johnson.lisa@countyofdane.com or see me at the Extension Booth at the front of the hall