Ironwood Capital | Capital. Simplified. | Avon, CT ironwood capital Ironwood Capital is a Connecticut-based private equity firm that provides non-control growth capital to middle market companies, investing more than $700 million in over 125 companies over the past 16 years. Ironwood invests in the form of subordinated debt and preferred stock in amounts ranging from $5 million to $20 million to support business owners and financial sponsors in growth financings, full and partial recapitalizations, generational transitions and buyouts.