Depending on the niche/industry your business is in, it can take anywhere between 1 to 6 months to see results with your content.
Some crucial factors that influence the success of a blog are:
- How competitive/saturated your niche is
- The number of quality backlinks you have
- The Domain Age and Domain Reputation of your website
- How much content do you plan to put out monthly (more content = faster results)
Having said that, most of my clients have gotten results on average after 3 months of working together.