Many times I've been asked the question: What does it mean when I have no planets in a house?
It's extremely common to have empty houses, being that there are, in general, only 10 planetary bodies in a chart and 12 houses!
The house location of the actual planets, as well as the nodes of the moon and any other planetary bodies that you may find of interest, are important because they show where there is a lot of activity in your life, and what sort of activity it is. But the empty houses tell a story too. Imagine you have no planets in your 7th house. That doesn't mean that you don't have any relationships! If you were to have an empty 7th house, for example, but you had a great concentration of planets, say, in the 4th house, this would mean that much of your attention and activities would be focused on your own personal inner work and development of your emotional self. Relationships in your life are always relevant, and are always growth intensive, but in this case, it might be only so far as they help you to discover your inner self through their impact on your life.
To discover the story that the empty houses in your chart have to tell you, look to the sign on the cusp of the house. The pertinent cusp is the beginning of the house. This, for instance, is how to determine what your ascendant (rising sign) is, by looking at the sign on the cusp of the first house. Can we deny the importance of the ascendant even if there are no planets in your first house? So look to the sign on the empty house cusp. The sign will tell you something about how you approach that area of life. Gemini on the 7th house cusp? You are likely to draw people to you that compel you to learn and ask questions in a way you never have before. Capricorn on the 11th house cusp? You need to approach your future with a sense of order and a structured plan for accomplishment of your goals.
There is also more to this story. Each sign has a planetary ruler (see the next section for a definition). The sign on the cusp of an empty house has a planetary ruler and it is somewhere in your chart. Further analysis of this ruling planet's location will help you understand more about how you approach the activities of the empty house. The activities in one house and their 'flavor' (sign & planets involved) are intertwined in your life -- the house with the ruling planet in it can act as the doorway to the 'empty' house and vice versa. So to use my earlier examples, let's say Gemini is on your 7th house cusp and Mercury (Gemini's ruling planet) is in your 10th house in Virgo. You would likely draw partners to you (7th house) that would encourage you to explore and ask yourself questions (Gemini) about who you want to be and what service (Virgo) you want to give to the world that is meaningful to you (10th house).
The example with Capricorn on your 11th house cusp -- let's say Saturn (Capricorn's ruling planet) is in your 2nd house in Aries. You may find that the people you find that you want to align yourself with (11th house) are people that have a certain maturity about them (Capricorn), and that by their encouragement and example, you gain a stronger sense of your own personal abilities and resources (2nd house), and can find the courage (Aries) more easily to test your own abilities, which can be naturally difficult for you while dealing with insecurities (Saturn) about your own ability to care for and do for yourself without help (Aries, 2nd house).
Use this technique to uncover even more understanding about the empty houses in your own chart.