Master Gardener Small Fruits in the Home Garden. Fruit Trees. Small Fruits. Small Fruits. Major limitation. Major limitation

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1 Master Gardener Small Fruits in the Home Garden M. Elena Garcia Ph.D. Fruit Trees Growing fruit trees in the home garden Pruning and training Why? Small Fruits Small Fruits Home Production small space perennial production some have few pests (except grapes) quality assurance landscape component home processing no special equipment needs for many of the crops health value Major limitation Winter Minimum Extremes Vermont in hardiness zones 3, 4 and 5 usually determined by latitude, weather fronts, hard to avoid depends on how cold, duration, prefreeze environment (hardening) advective freezes - large air mass movements Major limitation large differences in hardiness in species, some difference in cultivar health of plant contributes to hardiness avoidance measures - burying canes, mulching, snow cover cold can damage buds, shoot tips, canes, crowns, whole plants crop tolerances 1

2 Chilling hour requirements Vermont Hardiness Zones Major limitation Spring Frosts short duration result of inversion temperatures of 30 to 25 F commonly damage is due to tissues exposed to surrounding cold Site Selection FROST RISK EXAMPLES HIGH RISK: Strawberries - bloom early, flowers damaged below 30 F, can frost protect with sprinklers MEDIUM RISK: Grapes - shoots can be damaged at 27 F, LOW RISK: Highbush blueberries - bloom later, flowers hardy to 23 to 25 F Critical temperature - minimum temperature that buds, fruit or flowers will endure for short periods without injury. Survey Soil conditions Sun exposure Available space Frost pockets Make a Map!! 2

3 Site selection Soil conditions Ideal soil for Small fruits Depends on the crop well drained medium loam acidic for blueberries Soil Conditions ph Site selection Range Availability of elements Test your soil ph before planting Soil fertility Site selection Soil amendments peat moss, lime,organic matter, or mineral elements Site selection Soil conditions Drainage Soil type clay sandy hardpan Best soil: Sandy loam Blueberries Family: Ericaceae Subfamily: Vacciniaceae Genus: Vaccinium Other Subgenera or Sections are: 1) Batodendron - sparkleberry, farkleberry, deerberry 2) Euvaccinium - bilberry, whortleberry 3) Oxycoccus - cranberry 3

4 Blueberry species 26 species exist in N. America, also in Europe, South America Often hybridize Good colonizers High bush ~ 5-23 ft Low bush < than 3 ft Rabbiteye up to 33 ft Blueberry species are variable 1) temperature tolerances - both high and low extremes 2) chilling hours required to break dormancy 3) water requirement 4) soil requirement - ph organic matter 5) plant size - l' to 30' 6) fruit characteristics - size, color, flavor 7) vegetative spread - crowns or rhizomes 8) Temperate species derived from tropical species Buds and shoots Shoots contain flower buds (toward the distal end) and vegetative buds below the flower buds; all formed in the axils of leaves Flower buds form on current season's growth, Flower buds for next year's crop are very noticeable toward the end of the growing season and number 5-7 shoots flower bud differentiation is basipedal usually produce several flushes of growth, after which the meristem aborts Blueberry roots Blueberry roots are fine and fibrous, and have no root hairs adventitious from rhizotomous activity roots are usually shallow and remain within the drip line of the plant root system distribution is limited by soil moisture and organic matter endotrophic mycorrhiza (fungus) can inhabit roots, contributing to: symbiotic relationship; the result is an aid to the plant in: 1) N availability, and 2) water absorption Inflorescence and flowers The inflorescence is a raceme Flowers are urn-shaped and are inverted epigenous Calyx forms a tube to which the ovary is united and remains on the fruit until maturity Corolla is made up of 5 petals which are fused Stamens number 8-10 and are shorter than the style Inflorescence and flowers Flowers open first at the base of the raceme Nectaries are present at the base of the ovary Flowers require bees to pollinate; bumblebees are best Rabbiteye blueberries require cross pollination; highbush are self-fruitful 4

5 Blueberry Morphology Ripening stages Stage Description Immature green Berry hard, dark green over 100% of the fruit surface Mature green Berry softer, light green over 100% of the fruit surface Green-pink Primarily light green, some pink showing at calyx end Blue-pink Primarily blue, some pink showing at stem end Blue Nearly completely blue, very little pink immediately around the scar Ripe 100% blue coloration Blueberry Fruit Fruit ripening A true berry ripens 2-3 months after bloom color varies from blue to black and pigment is found in epidermis and the hypodermis covered with a waxy cuticle which helps prevent drying - known as "bloom" Blueberry Cultural Requirements Site selection Northern limit of production determined by Length of growing season (160 days minimum) Min winter temperatures North facing slope may delay flowering Soil is critical and considerations are: ph - acidic soil required, preferably with a ph of must do soil test - can acidify with sulfur Planting Time: In Spring when danger of hard freezes is over Plant types - 2 year old or large 1 year old rooted cuttings 1) container grown - may need to score root system 2) bare root - must plant prior to the end of the dormant season Do not let the roots dry out while handling or planting 5

6 Planting procedure 1) Prepare the whole field or a 6' strip; plow, disc, subsoil 2) Dig the hole with a shovel or open a furrow; avoid an auger digging device 3) Add 1 gallon or more of peat moss to the planting hole ½ at the base and mix ½ with the fill soil around the plant (wet peat moss) 4) Plant at the same depth as grown in the nursery 5) Do not fertilize at planting Spacing 4' between plants x 10' between rows for highbush = 1089 plants/acre; some growers spacing closer (3' common) Remove all flower buds at planting Mulching recommended for all blueberries; not as much response on rabbiteyes materials are sawdust, pine needles, etc.; straw will break down quickly should be surface applied in the row following planting, and kept at a 6" depth may need to add extra N Values of Mulching 1. Helps keep soil cool in summer 2. Helps retain soil moisture 3. Adds organic matter, helps in nutrition probably 4. Improves soil structure 5. Helps reduce weed pressure Do not incorporate the mulch in the soil Nutrition Blueberries are unusual in that they are not "heavy feeders" for elements Common fertilizer needs: 1) N should be applied each year; usually best to apply 3 times: When growth begins, budbreak and 6, 12 weeks later 2) K needed some years; heavy crop removes more K 3) P usually not needed; can be detrimental; 4) Sometimes needed are: Mg, Fe Key component of fertility management is soil ph- General Fertilization Guidelines 1st Year none applied at planting fertilize 3 times (budbreak and 6, 12 weeks later use complete fertilizer if P and K needed 2nd Year apply N at budbreak and at 6 & 12 weeks later apply other materials if other elements are needed 6

7 General Fertilization Guidelines 3rd year and older continue N applications 3 times/season total N should be lb/acre non-mulched plants probably need only the lower rate Nutrition problems Most common foliar problem chlorosis caused by: 1. ph too high or low 2. high Ca soils 3. Fe antagonist such as Mn or other cation Correct by: 1. monitoring ph closely - adjust if needed 2. using Fe chelate spray Blueberry Irrigation It is Essential For Plant Survival and Production leaves have high resistance to water loss low transpiration rates usually need approx. 1"/week, not delivered at one time trickle or drip system is the most common method in Vermont; ~1 or 2 emitters/plant used; spaced every 2' and delivery of ½ gallon/hour probably best high calcium or high ph water - can be detrimental Blueberry Pruning Concepts 1) Pruning is done to balance the fruiting and growth for the following year. 2) Excess pruning will increase fruit size, but decrease yield 3) Under pruning will result in smaller fruit and less new growth for next year's crop, although higher current season yield 4) Thicker stems usually produce more and larger fruit Blueberry Pruning Pruning in years 1-4 remove flower buds in years 1 and 2 remove small, twiggy growth at the base of the plants (optional) objective is to encourage maximum growth for years 1 and 2 Blueberry Pruning Mature plants - 5 years and older 1. Remove all twiggy or short growth from the base of the plant 2. Remove any dead wood 3. Remove approximately 1 cane (at the plant crown) for every 6 canes present. Choose the oldest cane for removal. Usually a maximum of 3/plant removed. 4. Thin out brushy growth in the upper (fruiting) portion of the plant. Time of pruning - dormant season; late winter best to allow removal of any winter kill 7

8 Strawberry Family: Rosaceae Genus: Fragaria 15 species F. x ananassa - the cultivated strawberry; a hybrid of F. chiloensis and F. virginiana History of Strawberry Production Mentioned in the history of the Romans - wild plants used only, not cultivated Cultivation first started in the 14th Century in France, and became widespread in the 15th century, using F. vesca 16th century - was a common garden plant in Europe In America, native Americans used F. virginiana for drying and making meal; Early settlers found this species and the first plants taken to Europe were to France in 1624; Later, this species was introduced to England and became the most popular species History of Strawberry Production F. chiloensis was brought from Chile to France by Francois Frezier in 1717; 5 plants survived the trip These plants produced little or no fruit but grew vigorously; It was determined that Frezier had brought female plants only Antoine Duschene discovered that the pollination of F. chiloensis with pollen from F. virginiana resulted in fruit production - Hybrids were found, which were larger fruited (from F. chiloensis) and of good quality (from F. virginiana) - Commercial strawberry production in the U.S. began about 1800, in the Northeast, using native F. virginiana Strawberry Morphology Crown - the compact stem which bears the leaves and axillary buds axillary buds can develop into a runner, inflorescence or branch crown. This development is based on the environment and nutritional status of the plant. older crowns become somewhat woody, and continue to grow from axillary buds produced at the terminal part of the crown. Strawberry Morphology Runners - stolons which originate from axillary buds in the crown produce "daughter" plants at the terminal of the stolon stolon rooting is known as "pegging" runner production varies as to cultivar and environment and is encouraged by long days and warm temperatures Strawberry Morphology Leaves- trifoliate, serrated arranged in a spiral around the crown, each sixth leaf above the first can be evergreen usually live for 1-3 months have numerous stomata and large internal cell areas which contribute to high water requirements 8

9 Strawberry Morphology Roots- arise adventitiously (at random, not by design) from the base of leaves on the crown primary roots live for up to one year the central vascular cylinder of the root is known as the "stele" 50-90% of roots are in the upper 6" of the soil Strawberry Morphology Inflorescence and Flowers the main stem of the inflorescence is the peduncle; the pedicel supports the individual flowers or fruits inflorescence is a cyme usually are subtended by bracts flowers are identified as one primary (largest fruit potential), two secondary, up to four tertiaries and possible additional flowers (usually produce very small fruit) flowers are perfect on cultivated types, early developing flowers more fertile but pollen less abundant pollination occurs by wind or insect (bee) transfer Strawberry Morphology Fruit- the commercial, edible fruit is an aggregate type, not a berry the achene is the actual fruit, containing the seed fruit development period is days after pollination; mean development period = 30 days fasciated fruit - misshapen fruit which are often flat Strawberry morphology fruit size is dependant on achene number and size due to hormone production during achene development Strawberry- Cultural Practices Soil salt problems can be critical; usually from previous fertilization ph range of light soils (sandy loam, etc.) best; high organic matter preferred if soil was previously covered with sod, white grub worms are a potential problem best to cultivate field the season or before or plant a crop not a host for grubs Strawberry- Cultural Practices Drainage air and water drainage essential; choose a site higher than the area around it if possible poor drainage can lead to root diseases Slope southern slope is usually earlier ripening, but greater frost risk Avoid steep slopes (higher than 5%) A source of high-quality water 9

10 Plant Selection Ripening season Disease resistance Adaptation of cultivar Performance of cultivar Certified virus tested The predominate plant type is the dormant crown Planting depth: Critical point Plants must be set with the growing point above the ground but with all roots covered; common problem Soil must be firmed around the plants to prevent soil from eroding away from the roots and resulting in root exposure Strawberry Fertilization initial application done at planting - applied under the beds apply annually just before flower bud formation in late summer (late August-early Sept.); usually broadcast - try to avoid wet leaves rate based on soil test but commonly lb/acre usually apply after renovation fertilization in spring is usually a mistake - leads to excessive growth and increases fruit rots and soft berries Blossom removal dormant plants set in the spring contain flower buds; these buds will develop flowers and fruit and compete with the vegetative activities of the plant such as leaf area, runnering and ultimately daughter plant establishment inflorescences should be pinched off; pulling off can result in the plant being dislodged from the soil Irrigation is required for reliable production important at the following times I) after transplanting - settles soil 2) early season encouragement of runnering and pegging 3) summer season to keep plants healthy and avoid loss 4) fall - flower bud initiation 5) spring - frost damage prevention during bloom 6) after renovation - encourage runner establishment usually 1"/week needed; more can be wasteful due to shallow root system Strawberry cultural planning year summary schedule Cultural Plant dormant crowns April or May Weed control Remove flowers Fertilize Position runners Weed control Fertilize Weed control Mulch May June or July June June-Sept. August September November Late November 10

11 Seasonal Growth Cycle in Vermont Late Summer and Early Fall flower bud initiation occurs in Fall due to: 1) day length of 15 hours or less (short days 2) temperature F or less initiation continues until dormancy (sometimes a slight amount during dormancy) Seasonal Growth Cycle in Vermont Early Spring vegetative growth resumes and flower clusters emerge, usually in April Spring flowering begins fruit ripens and harvest season complete (usually days), depending on temperature Summer vegetative growth occurs, with prolific runnering to form a new bed following renovation cycle begins again in late August Flowering Types Single croppers or Junebearers respond to short days and produce one crop many cultivars can be made to flower more continuously if grown in cooler temperatures the most common type in the East Flowering Types Everbearers actually produce 2 main crops: one in the Spring and one in late Summer often do not produce many runners not usually commercially important; 'Tristar' and 'Tribute' are more recent introductions Flowering Types Day Neutrals multiple cropping types do not depend on day length for flower induction; long day plants; becoming more common in many new cultivar development programs Cold damage susceptibilities 1. primary or king flowers open first and are the most difficult and critical to protect 2. small, developing fruits are killed at about 29 F 3. open flowers are killed at 26 F 4. unopened flowers are killed at F 11

12 Strawberry Harvesting Fruit does not improve in quality after harvest; sugar and acid remain at similar levels but color will develop should pick fields every 2 days - harvest in the morning during cool temps. pick by breaking the pedicel, not pulling caps remove fruit from the field to a cool area storage up to 7 days at 30 F is possible harvest period is usually 3 weeks/cultivar Brambles (Raspberries and Blackberries) Raspberries Family: Rosaceae Genus: Rubus L. Roman: ruber =red Subgenera: Rubus - blackberries and dewberries: fruit with receptacle (torus) Idaeobatus - red and black raspberries: fruit hollow, receptacle remains on the pedicel Species: more than 700 exist, found in all geographic regions except very dry deserts Rubus characteristics 1. perennial herbaceous shrubs (root system is perennial) 2. canes are biennial: 1st year growth is a primocane (vegetative) 2nd year is a fioricane; dies after fruiting 3. canes are trailing, semi-erect or erect 4. canes have prickles (thorny) or are smooth (thornless) Rubus Characteristics 5. calyx is 5 parted and white petals usually number 5 and are deciduous 6. inflorescence varies from racemose to cymose 7.f lowers are usually perfect, with many pistils and stamens 8. edible fruit is made of united pistils to from an aggregate fruit; actual fruit is a drupelet which contains the seed Rubus characteristics Species hybrids of Raspberry and Blackberry Boysenberry, Loganberry and Youngberry all are hybrids of red raspberry and blackberry are considered to be blackberries due to fruit structure- 12

13 Fruiting habit of cultivated Rubus Primocane. Vegetative, first year growth Growth begins in the spring Buds form at the leaf axils Axillary buds begin to differentiate when the terminal bud stops Fruiting habit of cultivated Rubus In some species of raspberries, primocanes will flower in the fall fruiting or fall fruiting More common in red raspberries, seen in some black and purple raspberries growing at the end of the season Fruiting habit of cultivated Rubus Raspberry morphology Floricane fruiting (second year of growth of the primocane): Blackberries Black and Purple Raspberries - usual type The number of nodes having flowers and the number of flowers per node depend on cane vigor and weather conditions in the fall Productivity of a cane is correlated to floricane diameter General Guidelines in Adaptation Blackberry not adapted to areas with extreme winter cold; this limits production in North U.S. not adapted to hot, dry windy plains can withstand fluctuating temperatures of the South Raspberry are adapted to cold climates; up to -50 F survival not adapted as well to hot climates fluctuating winter temperatures are a problem in the South, since they have a short rest period and leaf out too early Planting Raspberries plants, space 2-4' apart; set at same depth as grown in the nursery virus free plants very important in raspberry planting plant during the dormant season; late winter or early spring best make sure plants are received moist; keep moist while planting 13

14 Irrigation Red Raspberries extremely important the first year; water stress usually can be limiting on stand establishment 1"/water per week best drip or sprinkler application OK although not essential to irrigate, yield, growth, and next year's crop can be affected are erect-growing but usually are supported by some type of trellis supports include: a) single stake - no wire b) single top wire with 2 lower training wires c) two top wires with or without a crossarm and 2 lower training wires Primocane Fruiting Red Raspberries fruit is harvested in the fall following harvest, canes are mowed; no manual pruning or topping canes regrow the next year for the fall crop another option is to prune the second-year canes (floricanes) back the area of fall fruiting and allow a summer crop to develop - crop will be good for homeowner 14