The 5th house governs love, romantic relationships, sex, physical pleasures, speculative investments, creativity, sexual assaults, kidnapping, children, etc. It also has an influence over friends, social connections, etc.
Mercury in the 5th house can have varying impacts depending on the zodiac sign He is posited in.
One certain factor is that if Mercury is well-placed in the 5th house, the person will be creative and may create a career based on their creativity. They will also have the chance to do well in finance and trading because speculative investments will bring them handsome returns.
If Mercury is posited in a zodiac sign of Mars (such as Aries or Scorpio) or the Sun (Leo), or the Moon (Cancer), or Jupiter (Sagittarius), or even Venus (Libra or Taurus), it will be able to provide all of its benefits to the native.
If Mercury is posited in a zodiac sign of Saturn (Capricorn or Aquarius), then they will be intelligent but they will have a difficult time finding their partner. Additionally, post-marriage, they may face some struggle in having children.
Some more considerations to note here:
- Mercury in exaltation (Virgo) – this is applicable for Taurus ascendants; Mercury in Virgo in the 5th house is exalted and will thus provide complete benefits to the ascendant unless afflicted. The person shall be creative and will also enjoy the happiness of children, meaning they will become a parent (hopefully only post-marriage); the progeny of such individuals will also revere and love them. Overall, an excellent placement unless Mercury is afflicted by a malefic in which case the person may have difficulty getting children.
- Mercury in His own sign (Gemini) – this is applicable for Aquarius ascendants; Mercury in this placement gives excellent wealth, but the person will have troubles becoming a parent or they may have to face delays. Additionally, such individuals tend to be dual-minded, though not necessarily in a negative way, because they will have trouble deciding what they wish to do and what they wish to not.
- Mercury in debilitation (Pisces) – this is obviously not a great placement for Mercury in the 5th house, because the person will face heartbreaks in their romantic ventures or love-related matters. They will also be too emotional in their relationships and rejections will make them overthink everything more and more, possibly also leading to stress and mental distress. However, any aspect of a benefic planet like Jupiter or Venus will ease things for the native and can help to reduce some of the negative effects of the same.
Any malefic influences here will either damage the effects of Mercury to help the native develop creativity and/or earn gains from speculative investments. If not that, it will affect the ability of Mercury to enable the person to have children. Conjunctions with planets like Rahu will cause issues to the individual if they are trying to have children but may give good returns on speculative investments if Rahu is in a favorable sign (Virgo, Gemini, Taurus, Libra, or Aquarius).