HYFM · Hydrofarm Holdings Group, Inc.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 1,667 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 334 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number

Includes 30,000 restricted stock units granted under the Issuer's 2020 Equity Incentive Plan which will vest on June 23, 2027.

Includes 30,000 restricted stock units granted under the Issuer's 2020 Equity Incentive Plan which will vest on June 23, 2027.

Includes 30,000 restricted stock units granted under the Issuer's 2020 Equity Incentive Plan which will vest on June 23, 2027.

Includes 30,000 restricted stock units granted under the Issuer's 2020 Equity Incentive Plan which will vest on June 23, 2027.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 17,500 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 3,333 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 1,666 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 3,333 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number

The reporting person received an award of 20,000 restricted stock units on October 1, 2025 which vest on June 9, 2026. Each restricted stock unit represents a right to receive one share of common stock upon vesting.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 166 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 834 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 1,167 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 1,500 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 333 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 1,667 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Includes 30,000 restricted stock units granted under the Issuer's 2020 Equity Incentive Plan which will vest on June 9, 2026.

Shares beneficially owned has been adjusted to reflect the 1-for-10 reverse stock split effected February 12, 2025.

Includes 30,000 restricted stock units granted under the Issuer's 2020 Equity Incentive Plan which will vest on June 9, 2026.

Shares beneficially owned has been adjusted to reflect the 1-for-10 reverse stock split effected February 12, 2025.

Includes 30,000 restricted stock units granted under the Issuer's 2020 Equity Incentive Plan which will vest on June 9, 2026.

Shares beneficially owned has been adjusted to reflect the 1-for-10 reverse stock split effected February 12, 2025.

Includes 30,000 restricted stock units granted under the Issuer's 2020 Equity Incentive Plan which will vest on June 9, 2026.

Shares beneficially owned has been adjusted to reflect the 1-for-10 reverse stock split effected February 12, 2025.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 10,001 stock-settled performance stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 2,751 stock-settled performance stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 1,151 stock-settled performance stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 2,501 stock-settled performance stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 3,959 stock-settled performance stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 845 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 667 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

On April 5, 2024, Mr. Lindeman was granted performance stock units ("PSUs") under the Issuer's 2020 Equity Incentive Plan. Each PSU represents the right, upon achievement of certain specified performance-based vesting criteria, to receive one share of the Issuer's common stock. On February 28, 2025, the Board of Directors determined that certain of the performance-based conditions were met resulting in 3,959 PSUs earned by Mr. Lindeman.

On April 5, 2024, Mr. O'Brien was granted performance stock units ("PSUs") under the Issuer's 2020 Equity Incentive Plan. Each PSU represents the right, upon achievement of certain specified performance-based vesting criteria, to receive one share of the Issuer's common stock. On February 28, 2025, the Board of Directors determined that certain of the performance-based conditions were met resulting in 2,501 PSUs earned by Mr. O'Brien.

Shares beneficially owned has been adjusted to reflect the 1-for-10 reverse stock split effected February 12, 2025.

On April 5, 2024, Mr. Toler was granted performance stock units ("PSUs") under the Issuer's 2020 Equity Incentive Plan. Each PSU represents the right, upon achievement of certain specified performance-based vesting criteria, to receive one share of the Issuer's common stock. On February 28, 2025, the Board of Directors determined that certain of the performance-based conditions were met resulting in 10,001 PSUs earned by Mr. Toler.

Shares beneficially owned has been adjusted to reflect the 1-for-10 reverse stock split effected February 12, 2025.

On April 5, 2024, Mr. Parker was granted performance stock units ("PSUs") under the Issuer's 2020 Equity Incentive Plan. Each PSU represents the right, upon achievement of certain specified performance-based vesting criteria, to receive one share of the Issuer's common stock. On February 28, 2025, the Board of Directors determined that certain of the performance-based conditions were met resulting in 2,751 PSUs earned by Mr. Parker.

On April 5, 2024, Ms. Ackerman was granted performance stock units ("PSUs") under the Issuer's 2020 Equity Incentive Plan. Each PSU represents the right, upon achievement of certain specified performance-based vesting criteria, to receive one share of the Issuer's common stock. On February 28, 2025, the Board of Directors determined that certain of the performance-based conditions were met resulting in 1,151 PSUs earned by Ms. Ackerman.

Shares beneficially owned has been adjusted to reflect the 1-for-10 reverse stock split effected February 12, 2025.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 167 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares beneficially owned has been adjusted to reflect the 1-for-10 reverse stock split effected February 12, 2025.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 334 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares beneficially owned has been adjusted to reflect the 1-for-10 reverse stock split effected February 12, 2025.

The reporting person received an award of 250,000 restricted stock units on January 1, 2025, vesting in three equal annual installments beginning on January 1, 2026. Each restricted stock unit represents a right to receive one share of common stock upon vesting.

The reporting person received an award of 350,000 restricted stock units on January 1, 2025, vesting in two equal annual installments beginning on January 1, 2026. Each restricted stock unit represents a right to receive one share of common stock upon vesting.

The reporting person received an award of 100,000 restricted stock units on January 1, 2025, vesting in three equal annual installments beginning on January 1, 2026. Each restricted stock unit represents a right to receive one share of common stock upon vesting.

The reporting person received an award of 100,000 restricted stock units on January 1, 2025, vesting in three equal annual installments beginning on January 1, 2026. Each restricted stock unit represents a right to receive one share of common stock upon vesting.

The reporting person received an award of 50,000 restricted stock units on January 1, 2025, vesting in three equal annual installments beginning on January 1, 2026. Each restricted stock unit represents a right to receive one share of common stock upon vesting.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 86,706 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 309 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 309 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 309 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $0.4944 to $0.4987, inclusive. The Reporting Person undertakes to provide, upon request by the SEC staff, the Issuer or a security holder of the Issuer, full information regarding the number of shares of common stock purchased on such date.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 8,333 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 15,000 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number.

Shares withheld to satisfy tax withholding obligation applicable to the vesting of 1,667 stock-settled restricted stock units, which may be settled, on a 1-for-1 basis, only in shares of common stock. Fractional amounts have been rounded to the nearest whole number