Hardwood is useful material in Stardew Valley, it is required for building farm buildings, house upgrades, it is also needed as a part of Construction Bundle at Community Centre. But not only that. Hardwood is part of quite many recipes. Crafting will require hardwood, not in great quantity, though.
All in all, you will find where to use this material. What you will also found, is a constant lack of it. So how do you get Hardwood in Stardew Valley?
First of all, you have to know that to get hardwood you will have to use Steel axe or better. Meaning you will have to upgrade your axe twice before being able to cut down hardwood. Go to Clint and ask him to upgrade your tools. First upgrade will upgrade your tool to Copper Axe (the upgrade requires 2 000 g and 5 Copper Bars). After upgrading your axe once you can get Steel Axe upgrade (the upgrade requires 5 000 g and 5 Iron Bars). Once Clint upgrades your axe, you will be ready to get some hardwood.
Hardwood comes from large stumps and logs. You will see several of those laying around in your farm. But once you cut them, they do not regenerate, so you will have to look for alternate hardwood sources in Stardew Valley.
There will be regenerating hardwood stumps in the Secret Woods. The entrance to this place is blocked by a huge log (which will also provide you with hardwood), you can get it out of your way once you upgrade your axe to Steel. In the Secret Woods you will find six large stumps that appear there again every day. One stump provides you with 2 pieces of hardwood, meaning you can get at least 12 pieces of hardwood everyday.
Some hardwood can be found inside the boxes down in the Mines. But that is not a reliable source since it’s uncertain whether or not you are going to find any hardwood there.
If you play on the Forest Farm map there will be 8 large stumps that can provide you with hardwood and regenerate every day on your farmland. Add this to the amount you can get in the Secret woods and you get quite a decent quantity of harwood.
