When should you put a picture with your blog posts?

I always include an image with each blog post. For me, it's part of making the best presentation possible. Adding images is extra work (Sometimes, I swear I spend more time sourcing the "just right" image than I do writing the post!), but I think that the effect they have on the overall "package" is worth it.

Here's my list of reasons why including images is a good idea:
1. Your reader's eye will be drawn to an image - giving you that much more time to grab his attention.
2. If you pick the right image, it can be worth even more than a thousand words. Great images help you add context, personality, color, and even layers of meaning to your text.
3. It's aesthetically pleasing. If you think looks don't count, you're just deluding yourself. We judge people and books by their "covers" all the time - the same goes for blogs.
4. It conveys your sense of professionalism and attention to detail. When I see a blog without images, I feel like the publisher is slacking off. Should the content be able to stand on its own? Of course, but the complete package (including a great image) has a higher perceived value.
5. It gives you an extra SEO opportunity with captions, labels, and meta data.
6. It gives you a chance to show off your creativity. Depending on what industry you're in, this is just icing, or critical to your core business. Imagine a designer's blog without images, for instance - doesn't make any sense. What about a financial consultant's blog with great images? Makes me think that this person might be able to think outside the box and offer creative solutions to my problems.
7. It's just fun. For all the extra time I spend finding the right image, I actually enjoy the process of adding that visual layer to my content. Plus - taking an image sourcing "break" in the middle of my day gives me a little visual vacation!

My suggestion would be to place images in blog posts whenever possible (even if it isn't "the perfect" image) - there is plenty of research, anecdotal and market based, to suggest that image based posts get read more - but the best indicator is your own personal reaction. Are you more likely to read an article with a photo and caption, or one that you have to comb through the first few sentences to figure out if it is really of interest to you?

In most cases, unless the text is a very short paragraph, with a very descriptive title - including an image to draw the eye and help explain the contents of the article is preferable. With most people in and out of articles and web pages all day, getting your message across quickly with an image to pull them in is almost always a best practice.

Whenever appropriate, include an image or video. It increases engagement and may improve rankings.

All blog posts should include some form of image, photo, cartoon, video, etc. The truth is, many people decide whether or not they will read a post based on the image, so we need to remember the phrase, "a picture is worth a thousand words." The image doesn't need to be placed at the top/beginning of a post, it can appear mid-way through it. But, the image will capture people's interest and curiosity, and it will also get them to start thinking about your blog post's title - and develop some interest in the content.