Sweet peas love cool weather; it might be getting too hot for them in Philly now. If you'd like to try, however, you can transplant them outside in part shade, in well-drained soil (not clay). They like sunshine, but they like cool soil. Organic mulch will help that, but certain mulches can also harbor slugs, especially the coarser materials such as bark mulch or straw. Fine organic matter isn't as attractive to slugs. You can also try planting your sweet peas in containers outdoors, using the potting soil etc. that you have. In the heat of the afternoon, provide some shade for them, or wheel them into a shady spot. In the fall, you might try planting more seeds outdoors--they should flower in spring, just when it's perfect weather for them.
For more information about sweet peas, you might be interested in:
Sweet peas love cool weather; it might be getting too hot for them in Philly now. If you'd like to try, however, you can transplant them outside in part shade, in well-drained soil (not clay). They like sunshine, but they like cool soil. Organic mulch will help that, but certain mulches can also harbor slugs, especially the coarser materials such as bark mulch or straw. Fine organic matter isn't as attractive to slugs. You can also try planting your sweet peas in containers outdoors, using the potting soil etc. that you have. In the heat of the afternoon, provide some shade for them, or wheel them into a shady spot. In the fall, you might try planting more seeds outdoors--they should flower in spring, just when it's perfect weather for them.
For more information about sweet peas, you might be interested in:
http://www.reneesgarden.com/articles/swp-direct-tips.html
For more information about how to control slugs, this video gives several tips and methods:
http://www.almanac.com/video/garden-pests-controlling-slugs-and-snails
And here are a few more tips on controlling slugs:
http://www.almanac.com/content/slugs
Hope this helps!