A narrow orb makes it uncommon
A sextile is sixty degrees, and the standard orb is about five, the tightest of the five major aspects. Venus and Mars pass through this angle twice per cycle, but the narrow allowance means the window is short, so fewer charts carry a sextile than carry a square or a trine between the same two planets.
The pair are two signs apart, which puts them in compatible polarities and different elements. Fire pairs with air and earth pairs with water. That is the mechanism the tradition relies on: not identity, as in a trine, but a workable difference.
Speed complicates the timing. When Venus is quick and Mars is slow, the sextile can be over in days. Near a Mars station it can hold considerably longer, and the resulting group of births share the contact.
Available rather than automatic
Venus is preference and Mars is the drive that follows it. A sextile means those two can be brought into line without much difficulty when you decide to. Nothing forces the issue, and nothing supplies the result unasked, which is why sextiles are so often described as latent.
What the aspect is credited with, when it is used, is a certain competence in wanting things. You can generally match the level of effort to the size of the desire without the two getting out of proportion, and you can drop a pursuit when it stops being worth the trouble. That is a modest claim, and modest is the right register for this aspect.
Its practical value in a reading is usually as support for something else. The tradition treats sextiles as routes between more demanding configurations, so a Venus and Mars sextile that also touches a difficult square elsewhere is doing more work than the same sextile sitting alone.
Signs, houses and the small print
Fire with air makes it articulate. You can name what attracts you and the naming helps you go after it. Earth with water makes it practical and instinctive, where the sense of what is wanted and the sensible way to get it arrive together. Those two flavours cover every possible version of this aspect.
House positions do the rest. Venus in the seventh sextile Mars in the ninth is a very different picture from Venus in the second sextile Mars in the fourth. Because the general reading of a sextile is thin, the house pair usually carries more information than the aspect itself.
Where to set the threshold
Five degrees is the widest most astrologers will allow, and many work to three or four. At the outer edge a sextile is a footnote and can reasonably be left out of a reading. There is no reason to build an interpretation on a four and a half degree contact when the same chart has a two degree square waiting.
Retrograde states apply but do not transform it. A retrograde Mars in sextile to Venus reads as drive that surfaces on its own timing, and Venus retrograde suggests preferences that have been reconsidered at least once. Neither of those turns an easy aspect into a hard one.
The check above reports the exact separation, both signs, both houses and whether either planet was retrograde. That is enough to decide whether the sextile in your chart is a genuine feature or something to note briefly and set aside.
Questions people ask about this
Why is a sextile given a smaller orb?
By long convention the easier and smaller aspects are allowed less room than the major hard ones. A sextile at five degrees is already considered weak, which is why most astrologers work with three or four degrees in practice.
What does Venus sextile Mars offer?
A workable link between what attracts you and how you pursue it, available when you engage with it. The tradition describes sextiles as opportunities rather than as conditions, so the aspect describes a capacity, not a result.
Which elements pair up in a sextile?
Fire with air, or earth with water. The two signs share a polarity but not an element, which the tradition reads as compatibility without sameness. That mixture is what distinguishes a sextile from a trine.
Is it worth reading at all?
When tight, yes, particularly if the same planets are involved in harder aspects that the sextile can route around. At the edge of orb it is fair to treat it as a background detail and concentrate on stronger contacts.
How does it differ from Venus trine Mars?
The trine puts both planets in the same element and is read as ease already in place. The sextile pairs different elements and is read as ease that has to be taken up. The trine also carries a wider orb and more traditional weight.
Does the aspect say anything about attraction to others?
Only indirectly. It describes how your own preferences and drives get along, which affects how you approach people without describing who they are. For contacts between two charts, a synastry comparison is the appropriate tool.