Flowering and Fruit Characteristics of Black Walnuts: A Tool for Identifying and Selecting Cultivars

Compare the nuts of walnut cultivars side by side


Growth characteristics of selected black walnut cultivars

Cultivar name
(Fingerprint alias)
BudbreakAverage first pistillate bloom dateMean pistillate bloom dateFirst pollen shed dateFlower typeSeason lengthHarvest date
BeckApril 28May 15May 21May 16Protogynous128 daysSept. 25
BowserApril 29May 9May 14May 19Protogynous128 daysSept. 17
Brown NuggetApril 16April 27May 1May 10Protogynous131 daysSept. 8
CranzApril 29May 19May 21May 11Protandrous130 daysSept. 27
Crosby2 May 2May 10May 19May 20Protogynous142 daysOct. 3
Davidson*April 12April 23April 28May 9Protogynous132 daysSept. 4
DrakeApril 28May 6May 13May 15Protogynous151 daysOct. 9
Elmer MyersMay 1May 10May 17May 23Protogynous128 daysSept. 18
Emma KApril 20April 23April 30May 6Protogynous148 daysSept. 23
FootballApril 15April 27May 1May 6Protogynous156 daysSept. 30
GrundyApril 20May 10May 12April 28Protogynous122 daysSept. 13
HareApril 29May 7May 16May 20Protogynous143 daysSept. 30
HarneyApril 27May 8May 15May 16Protogynous133 daysSept. 26
HayMay 5May 14May 22May 24Protogynous135 daysOct. 3
Higbee MillMay 4May 17May 27May 25Protogynous131 daysOct. 2
JacksonApril 16April 27May 2May 9Protogynous155 daysSept. 28
KnuveanApril 18May 11May 17April 29Protandrous136 daysOct. 1
Kwik KropApril 26May 5May 9May 18Protogynous148 daysOct. 3
MintleApril 17May 14May 19May 1Protandrous129 daysSept. 23
MystryApril 16April 29May 4May 11Protogynous141 daysSept. 19
Neel #1May 3May 12May 21May 21Protogynous141 daysOct. 5
NessApril 16April 27April 30May 10Protogynous168 daysOct. 12
OgdenApril 23May 6May 10May 13Protogynous168 daysOct. 18
OhioApril 24May 7May 8May 15Protogynous140 daysSept. 18
(Emma K)
April 16April 25April 30May 6Protogynous153 daysSept. 28
Pound #2April 24May 8May 17May 20Protogynous143 daysOct. 1
PritchettApril 18April 28May 6May 12Protogynous134 daysSept. 14
April 28May 7May 13May 20Protogynous145 daysOct. 2
(Kwik Krop)
April 25May 4May 9May 15Protogynous141 daysSept. 25
Sauber #1April 26May 6May 14May 18Protogynous134 daysSept. 20
Sauber #2
 May 8May 14May 17Protogynous118 daysSept. 5
SchesslerApril 13April 22April 29May 6Protogynous129 daysSept. 4
April 27May 10May 14May 15Protogynous117 daysSept. 5
ShreveMay 2May 8May 17May 17Protogynous147 daysOct. 4
South ForkApril 14May 9May 6April 28Protandrous158 daysOct. 8
Sparks 127April 25May 7May 12May 16Protogynous118 daysSept. 4
Sparks 129April 23April 27May 6May 15Protogynous125 daysSept. 28
Sparks 147May 3May 11May 15May 18Protogynous131 daysSept. 21
SparrowApril 26May 11May 13May 16Protogynous119 daysSept. 6
SurpriseApril 25May 6May 10May 15Protogynous143 daysSept. 30
ThomasMay 2May 6May 15May 21Protogynous145 daysOct. 2
Thomas MyersMay 5May 11May 21May 21Protogynous131 daysSept. 26
TomboyApril 18April 27May 1May 9Protogynous135 daysSept. 10
WiardApril 28May 14May 24May 9Protandrous125 daysSept. 21
*Davidson cultivar is not pictured.

Characteristics definitions

  • Fingerprint alias
    Some cultivars with different names are genetically identical as determined by DNA fingerprinting. Where this occurs among the cultivars listed in the table, "cultivar name" is the name thought to have been assigned first; "fingerprint alias," later.
  • Budbreak
    The average date of budbreak is the time when the tips of leaves are visible from swollen buds. Female or pistillate flowers develop at the tips of the new growth, while male or staminate flowers are produced on catkins on one-year-old growth.
  • Pistillate bloom dates
    Pistillate bloom occurs over a period of several days. Thus, date of first pistillate bloom is important in selecting cultivars that will avoid injury due to late-season frosts. The mean (average) pistillate bloom date is when female flowers are most likely to be receptive to pollen.
  • First pollen shed
    Mean dates of pollen shed are important because these dates must coincide with pistillate bloom and receptivity for effective cross-pollination and subsequent fertilization to occur.
  • Flower type
    Black walnut cultivars exhibit two flowering habits. Protogynous cultivars are those that produce pistillate flowers before the staminate flowers. Protandrous cultivars produce staminate flowers on catkins before the pistillate flowers are visible.
  • Season length
    Season length is the number of days from the mean pistillate bloom date to the date of harvest.
  • Harvest date
    Average date of harvest is the date by which nuts are suitable for harvest.