I hear you! Summer can be a challenge when you have COPD, but with some adjustments you can and will enjoy it. Picnics can still be enjoyable especially if you can find a place to sit that's far from the fire and upwind of it. If you can, ask someone in the group you're with to fix a plate for you and bring it back to you - it'll save walking and getting too near the fire/smoke.
Depending on where you like to buy your plants and flowers, you could try a couple of modifications that may make it easier on you. First, pick a greenhouse or store that has nice carts to lean on or even the motorized wheelchairs. Don't be embarrassed - that's what they're there for. Also, go at a time of day when it might be a little cooler - early morning or evening. The crowds may also be better too; especially in the morning. Lastly, do try to do too much at one time. Get a few plants, take them home, rest, and then plant them when you feel up to it. If you want more, go back and get more. Pace yourself the best you can - it's much more enjoyable that way.
Take care and try to enjoy your summer!
Lyn (COPD site moderator)