This document provides guidance on plant nutrition for bramble plants such as raspberries and blackberries. Key recommendations include: 1. Conduct soil testing and amend the soil with lime, organic matter, and pre-plant nutrients based on the results. Maintain a soil pH between 5-6.5 for optimal nutrient availability. 2. Apply nitrogen, phosphorus, and potassium according to soil test recommendations, with most brambles requiring 50-100 lbs of nitrogen per year. Split nitrogen applications and consider fertigation for efficient delivery. 3. Maintain adequate levels of calcium, magnesium, boron, and other micronutrients through soil applications and foliar sprays as needed based on tissue

1. Bramble Plant Nutrition
Eric Hanson, Department of Horticulture
Michigan State University
hansone@msu.edu
517.355.5191 x1386

2. Pre-plant Considerations
1. Soil test for pH and nutrient levels
2. Organic matter addition:
cover crops, manure, compost,
other organic amendments

3. Optimum pH Range
Blueberry Brambles
4 5 6 7
1.Lime according to soil tests
2.Use dolomitic lime if Mg is low
3.Apply and incorporate a year before planting

4. Pre-plant Phosphorus and Potassium
Incorporate prior to planting; base rates on soil tests.
Fertilizer % P2O5 or K2O
Superphosphate 21
Concentrated superphosphate 45
Potassium chloride 60-62
Potassium sulfate 50-54
Potassium-magnesium sulfate 22 (11% Mg)

6. Gypsum may help control Phytophthora root rot
Gypsum (CaSO4) supplies Ca but does not alter pH. Gypsum
reduced raspberry root rot caused by Phytophthora spp. in
NY (Maloney et al., 2005) and WA (Pinkerton et al., 2009).
Gypsum has reduced other Phytophthora diseases.
High Ca concentrations specifically inhibit fungal growth
and infection of plant tissues.
Recommendation:
Incorporate 3-6 tons gypsum prior to planting raspberries
on sites with a history of Phytophthora root rot.

7. Pre-plant Manure and Compost Use

8. Average nitrogen fertilizer price trends in the US
(USDA, Economic Research Service)
1.20
Urea
$1.01
1.00 Ammonium nitrate
Ammonium sulfate
0.80
$/lb N
$0.58
0.60
$0.57
0.40
0.20
0.00
02 03 04 05 06 07 08 09 10 11
Year

9. Pre-plant manure and compost –
general considerations
Often beneficial, particularly on sandy soils, heavily farmed sites.
Analyze material before applying to avoid:
1. Excessive total salts.
2. Excessive P or N
3. N tie-up or excess (C:N above 30:1 tie up N)
4. Specific element toxicities (heavy metals, B, Na, Cl)
Apply and incorporate raw manure the fall before spring planting
Avoid manure or compost with salt levels > 10 dS/m.
Apply materials with salt levels of 5-10 dS/m in the fall to allow
salts to leach.

10. Manure Use – Avoid Excessive Soil P
(Michigan Manure GAAMP’s)
Know soil and manure P levels.
(Manure can vary from 10 lb P2O5 per ton to 45 lb)
If soil tests indicate P is needed, apply enough manure to
supply 100 to 200 lb P2O5/acre.
If Bray P1 test is 75 to 150 ppm, apply enough manure to
replace crop removal.
If the Bray P1 test is above 150 ppm, do not apply manure.

11. Variation in C:N and salt levels of Michigan composts (J. Biernbaum)

12. Learn from your mistakes:
To provide adequate nutrition for a new organic raspberry
planting under high tunnels, we incorporated 10 tons of a
fortified dairy compost in the rows before planting.

13. Injury to newly planted high tunnel raspberries from
compost incorporated before planting at 10 tons/acre.
Compost Analysis
EC
pH (dS m-1) C:N ratio N (%)
6.9 14.05 7.9:1 2.92

14. Raspberry Tissue Sampling
Collect 50-75 mature leaves from middle
of primocanes in August
Rinse briefly in tap water.
Dry on table top.
Send to reputable lab for nutrient
analysis.

15. Desired Leaf Nutrient Levels for
Raspberries and Blackberries
% PPM
N 2.0 – 2.8 B 30-90
P 0.25 – 0.40 Cu 7-20
K 1.5 – 2.5 Fe 60-250
Ca 0.7 – 1.7 Mn 50-200
Mg 0.3 – 0.5 Zn 20-50

16. Nitrogen Management
Nearly all brambles need N annually
For efficient N use, choose the right:
1. fertilizer
2. rate
3. timing
4. placement
Hart et al., 2006. EM 8903-E
Oregon St. Univ. Ext

17. N Fertilizers
Lime equivalent
Source %N Reaction (lb lime/lb N)*
Ammonium nitrate 32 acidic -1.8
Ammonium sulfate 21 acidic -5.3
Calcium nitrate 16 basic 1.3
Potassium nitrate 12 basic 1.9
Urea 46 acidic -1.8
DAP 17 acidic -4.1
MAP 11 acidic -3.5
blends variable variable variable
*Lb lime equivalent to alkalinity from 1 lb N (positive values) or
required to neutralize the acidity from 1 lb N (negative values)

18. Soil salt levels based on saturated paste extract
potentially causing yield reductions in fruit crops.*
Crop Soil EC (dS/m)**
Olives 2.7
Grapefruit 1.8
Apple/pear/peach 1.7
Apricots 1.6
Grapes 1.5
Blackberries 1.5
Raspberries/strawberries 1.0
Blueberries ??
*Western Fertilizer Handbook (1990)
**1 dS/m = 1 mmho/cm

19. Salt index values for some common N fertilizer
Salt index
Fertilizer %N Salt index* per unit N
Ammonium nitrate 33 105 300
Ammonium sulfate 21 69 328
Calcium nitrate 12 53 442
Di-ammonium phosphate 18 29 161
Mono-ammonium phosphate 11 27 245
Natural organic 13 3.5 70
UAN 28% 28 71 222
Urea 46 75 162
* Salt index is the increase in osmotic pressure resulting addition of fertilizer to a
solution, relative to affect of the same amount of NaNO3 (SI = 100).
After: Kamburova and Kirilov, 2008

20. N Sources and Rates
Sources
Urea and ammonium nitrate are usually cheapest and best.
Rates (lb/acre)
(higher rates on sandy soils and fall bearing types)
Yr 1 Yr 2 Yr 3 and older
20-40 30-60 50-100

23. N Timing – Brambles
1. Heavier, fertile soils: all at bud break
(April-May)
2. Sandy soils: half at bud break, half
3-4 weeks later
Bud break Harvest
April May June July August

24. Nitrogen Placement - Brambles
1st year plants Established plants
Apply in a 2-3 ft wide circle Broadcast
or a band or band

25. Potassium
Brambles have a high demand for K;
regular applications are usually needed.
Choose K sources based on:
1. conventional or organic
2. cost per unit of K2O
3. need for other nutrients
K deficiency (T. Wallace)
4. potential hazard from chlorine
K fertilizers % K2O Comments
Potassium chloride 60-62 Chloride hazard
Potassium sulfate 50-54 Moderate expense
Sul-Po-Mag 22 (11% Mg) Expensive

26. Potassium
Rates based on soil tests, generally:
100-200 lb K2O per acre to correct most shortages
50-100 lb K2O per acre for maintenance
Timing: anytime
Fall application is best for KCl (muriate) to allow
time for Cl to leach.
Excessive K use can cause Mg shortages.

27. Ca, Mg, K Ratios are important
Desired ranges for % of Bases
K
10-20%
Mg Ca
20-30% 60-70%

28. Phosphorus
Fertilizers % P2O5
Superphosphate 21
Concentrated superphosphate 45
Di-ammonium phosphate 46
Mono-ammonium phosphate 52

29. Magnesium and Calcium
Ca and Mg Sources % Mg % Ca %K
Magnesium sulfate (epsom salts) 10
Calcium sulfate (gypsum) 22
Potassium-magnesium sulfate 11 22
Calcitic lime <5 >30
Dolomitic lime >5 <30
If pH is too low, use dolomitic or calcitic lime.
If pH is appropriate, use gypsum for Ca, or epsom salts
or potassium magnesium sulfate for Mg.
Apply whenever need is determined.

30. Calcium and Fruit Quality
Elevated tissue Ca is often associated with improved quality:
- reduced incidence of some fruit disorders
(bitter pit in apple fruit)
- increased firmness (Ca inhibits enzymes that degrade cell walls
when tissues senescence).
- reduced rot caused several fungal pathogens
(Ca may inhibit fungal enzymes that degrade tissues)
Ca affects on raspberry quality:
- pre-harvest Ca sprays have increased firmness, prolonged
shelf-life, and/or reduced Botrytis rot, but not consistently.

31. Boron
Shortages may cause poor
shoot grown, reduced fruit set,
or fruit deformities
Brambles are sensitive to excess B;
apply proper rates if soil or leaf
analyses show a need.
Application options:
Foliar spray of 2 lb Solubor (20% B) per acre in June
Soil spray of 3 lb Solubor in spring.
Soil application of 5 lb borax (11% B) in spring.

32. Iron
Deficiencies only occur when soil pH is too high; best
treatment usually is to reduce pH.
Foliar sprays of Fe chelate products relieve some leaf
symptoms, but don’t usually improve vigor.

33. Manganese
Not often deficient. High soil pH limits availability.
Treatments (if leaf analyses indicate a need):
1. Check and reduce pH if it is too high.
2. Foliar sprays of manganese sulfate or Mn-chelates.
3. Maneb, Dithane, and Manzate fungicides contain Mn.
Zinc
Not often deficient. Most likely on sandy, high pH soils.
Treatments (if leaf analysis indicates a need):
1. Check and reduce pH if it is too high.
2. Apply foliar sprays of Zn sulfate or Zn chelate products.
3. Ziram fungicide contains Zn and can be a good sources

34. Copper, Molybdenum
Deficiencies have not been documented in Midwest or
Eastern brambles.
If leaf analysis indicate Cu is deficient:
Fixed copper fungicides (e.g. Kocide, Champ) are suitable
sources of Cu for labeled crops.
Copper salts can potentially injure tissues so test on a few
plants before using widely.

35. Fertigation
Injecting fertilizers through trickle
irrigation systems can be convenient
and efficient.
Most useful for delivering N and
sometimes K and P.
Advantages Disadvantages
Greater control over nutrient Capital costs: injector, tanks,
placement and timing backflow valve
Improved efficiency; less fertilizer Maintenance (tanks, line
required (if not over-irrigating) plugging) and calibration

36. Solubility of some common fertilizers
Fertilizer Solubility (lb/gal)*
Ammonium nitrate (33-0-0) 16.0
Ammonium sulfate (21-0-0) 6.2
Calcium nitrate 15-0-0) 11.2
Di-ammonium phosphate (21-54-0) 5.7
Mono-ammonium phosphate (11-48-0) 3.1
Urea (45-0-0) 8.8
Potassium chloride (0-0-60) 2.1
Potassium sulfate (0-0-48) 0.9
* At 70 oF. Solubility of all materials is lower in colder water.
1. Mixtures may reduce the solubility of some salts
2. Do not mix calcium with sulfates or phosphates. Use a “jar test”
to test for precipitates.
3. Soluble blended fertilizers may be easiest.

37. Suggested N Fertigation –Brambles
1. Reduce annual rate by 1/3
(assume improved efficiency)
2. Split annual rate into multiple applications starting
2-3 weeks after budbreak and continuing into August
BB Harvest
April May June July August

38. Fertigation is very efficient if:
1. Irrigation system has high uniformity
2. Nutrients are applied when demand is high
3. Plants are not over-watered (leaches nutrients).

39. 1. Utilize soil tests, leaf analysis
2. Follow local recommendations
3. Trying something new? Leave
non-treated “check areas”.
Questions, Comments??