I've always aimed for the lowest alpha in the alpha acid range, and frequently my tongue still says I'm coming up short on those brews in terms of IBUs. This is one of the instances I think it's good to set your sights low
Grassiness is a definite possibility in a fresh hop ale, especially if the amount of hops are significant; BUT, to me, it's par for the course. I expect a little grassiness from fresh hop ales and that's what I usually get. I'm okay with it. If you want to reduce the amount of grassiness then you can dry them for a day or two prior to brewing. The drying process allows some of the natural juices (not lupulin) in the cone leaves to evaporate which serves to reduce the grassiness. Since you're already drying them, you should be set.
Since I am using homegrown for bittering this is what I have for my hop addition. Right now beersmith says 105.8 using leaf hops at 13%AA. Dont know if this is too much for hops that will have been drying for 4 full days prior to using.
Recipe Specifications
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Boil Size: 7.74 gal
Post Boil Volume: 6.24 gal
Batch Size (fermenter): 5.25 gal
Bottling Volume: 4.85 gal
Estimated OG: 1.069 SG
Estimated Color: 6.3 SRM
Estimated IBU: 105.8 IBUs
Brewhouse Efficiency: 75.00 %
Est Mash Efficiency: 85.7 %
Boil Time: 60 Minutes
Ingredients:
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Amt Name Type # %/IBU
11 lbs 4.0 oz Pale Malt (2 Row) US (2.0 SRM) Grain 1 83.3 %
1 lbs Rye Malt (4.7 SRM) Grain 2 7.4 %
12.0 oz Cara-Pils/Dextrine (2.0 SRM) Grain 3 5.6 %
8.0 oz Caramel/Crystal Malt - 40L (40.0 SRM) Grain 4 3.7 %
1.75 oz Chinook [13.00 %] - Boil 60.0 min Hop 5 63.5 IBUs
1.00 oz Chinook [13.00 %] - Boil 20.0 min Hop 6 22.0 IBUs
1.00 oz Chinook [13.00 %] - Boil 10.0 min Hop 7 13.1 IBUs
1.00 oz Chinook [13.00 %] - Boil 5.0 min Hop 8 7.2 IBUs
1.00 oz Chinook [13.00 %] - Boil 0.0 min Hop 9 0.0 IBUs
1.0 pkg SafAle English Ale (DCL/Fermentis #S-04) Yeast 10 -
2.00 oz Chinook [13.00 %] - Dry Hop 0.0 Days Hop 11 0.0 IBUs