Short answer. Under Article 1075, fruits and income of collated property are counted against the estate only from the day the succession opened — that is, the day the decedent died. Income you collected from the land before that date belongs to you entirely and is not part of what you must bring into the collation.
What the law says
The fruits and interest of the property subject to collation shall not pertain to the estate except from the day on which the succession is opened.
Civil Code, Article 1075 — Fruits and Interest. Read the full provision →
What collation requires
Collation is the process by which heirs who received advances from the decedent during the latter's lifetime bring those advances into the common inheritance pool before shares are divided. The goal is equal treatment: an heir who received a large gift does not take a full equal share again at death unless the gift is accounted for. The value of the donated property is added back to the estate — figuratively — so that all heirs' shares can be computed on a common base. Article 1075 addresses a specific sub-question: what about the income the property generated between the donation and the death?
The cut-off date: succession opens
Article 1075 draws a clean line. Fruits and interest of collated property do not pertain to the estate except from the day on which the succession is opened. In the Philippines, succession opens at the moment of the decedent's death. Everything before that date — years or decades of crops, rents, dividends, or other income from the donated land — belongs to the donee-heir and is outside the scope of collation. The donee had the property legitimately, used and managed it, and kept the income during the decedent's lifetime.
How the post-death income is measured
Article 1075 also provides a method for assessing fruits and interest that do fall within collation — those arising after the succession opened. The measuring standard is the fruits and interest of property of the estate of the same kind and quality. In practice, this means you compare the collated property to similar estate assets and use the income those estate assets produced during the same period as the benchmark. This avoids disputes about the particular productivity of the donated land and applies a consistent standard across the estate.
Practical effect for a collating heir
If you received land years ago and have been farming it or renting it out, all those years of income before the decedent's death are yours. What Article 1075 requires is that, from the date of death, you account for the value of fruits and income the land generated as part of your collation. This usually matters most in estates that take a long time to settle, since income continues to accumulate on the donated property while the estate proceedings are ongoing. Keeping records of what the land produced after the decedent's death is useful for making that computation accurately.