One advantage you do have vs Soraka bot is that it's very hard for their jungle to successfully gank since Soraka has no follow ups.

Also, Soraka has a long CD on her heals. The trick is forcing the heal and acting between her heal CD's. Your skills will be up before her heal. You can also wait for Soraka to use her heal and blow all of your CDs on the target without the armor buff.

If you and your lane partner can not do that, then Soraka lane just snowballs because they always win extended trades without kills.

Trading with Soraka lane has to end with kills or summoners. Otherwise you can only play passive and farm until the jungle or mid comes down to gank.