Why is Mercury called neutral?

Because classical texts hold that it takes on the nature of the planets it associates with — benefic in benefic company, malefic in malefic company. This makes conjunctions unusually important when reading a Mercury period.

What does a combust Mercury mean for its mahadasha?

Mercury stays close to the Sun and is combust in many charts, which is generally read as weakening it. Some traditions read a Mercury with the Sun as Budhaditya yoga instead, so the placement is worth reading properly rather than applying a single rule.

What are the remedies during Budh mahadasha?

Tradition suggests the Budh mantra, donating green gram or green cloth on Wednesday, and care with speech and written commitments — Mercury governs both, and both are where its periods are usually felt first.

Budh (Mercury) Mahadasha

बुध महादशा

What happens during Budh mahadasha?

Budh mahadasha runs for 17 years. Mercury is the karaka of intellect, speech, commerce, writing and analysis. It is the most adaptable of the nine — classical texts call it neutral, taking on the character of whichever planets it sits with — so its period is read from its company as much as from its placement.

The planet that takes on its company

Mercury is classically neutral — benefic with benefics, malefic with malefics. A Mercury sitting with Jupiter behaves differently in its own period from a Mercury sitting with Saturn and Rahu. This is why a Budh mahadasha cannot be read from Mercury's sign alone; conjunctions matter more here than for most planets. Mercury is also the one planet exalted in a sign it owns, Kanya, which classical texts treat as a notably strong placement.

Combustion is a live question for Mercury

Mercury never travels far from the Sun, so it is combust in a large share of charts. A combust Mercury is read as weakened, and since these are seventeen years that matter, it is worth knowing before assuming an intellect-and-commerce period will simply deliver. Some traditions hold that a combust Mercury in the same sign as the Sun forms Budhaditya yoga instead — another reason to read the placement rather than apply a rule.

Trade, speech and the seventeen years

Mercury governs business, negotiation, contracts, writing and every form of exchange. Its dasha is often associated with commerce and with work that runs on communication. Where that actually lands depends on the houses Mercury occupies and rules — a Mercury ruling the tenth points the same seventeen years at profession, one ruling the third at siblings, courage and short journeys.

Common questions

How long is Budh mahadasha?: Seventeen years.
Why is Mercury called neutral?: Because classical texts hold that it takes on the nature of the planets it associates with — benefic in benefic company, malefic in malefic company. This makes conjunctions unusually important when reading a Mercury period.
What does a combust Mercury mean for its mahadasha?: Mercury stays close to the Sun and is combust in many charts, which is generally read as weakening it. Some traditions read a Mercury with the Sun as Budhaditya yoga instead, so the placement is worth reading properly rather than applying a single rule.
What are the remedies during Budh mahadasha?: Tradition suggests the Budh mantra, donating green gram or green cloth on Wednesday, and care with speech and written commitments — Mercury governs both, and both are where its periods are usually felt first.