df = pd.DataFrame([[2, 4, 5, 6, 1], [4, 5, 6, 7, 2], [5, 4, 5, 5, 1], [10, 
    4, 7, 8, 2], [9, 3, 4, 6, 2], [3, 3, 4, 4, 1]], columns=['bar',
    'prog +, DMSO+ 1', 'foo', 'something', 'prog +, DMSO+ 2'])
ax = sns.boxplot(data=df, orient='h')
boxes = ax.artists
for i, box in enumerate(boxes):
    if 'prog +, DMSO+' in df.columns[i]:
        box.set_facecolor('r')
else:
    box.set_facecolor('b')
plt.tight_layout()
plt.show()
Color seaborn boxplot based in DataFrame column name