Si clause with indicativo

Question

Hi,I was wondering why this sentence uses the indicativo in the si-clause:"me dijo que si la regaba y crecía como una planta, tendría un perro"Isn't the mom seeing this condition as something not at all likely to happen? Does not the use of the conditional in the main clause also indicate that it is less likely and therefore require the subjunctivo?Thanks!Deborah

Accepted Answer

Hola Deborah
Interesting and very useful question!
We need to see this sentence as it is: reported speech; this is reporting what someone else said before, so if we do that we have to consider that a person has previously said this:
Si la riegas y crece como una planta, tendrás un perro.
If you water it and it grows as a plant, you will have a dog.
You can see this "si" structure here in this lesson.
The original sentence would be using the present tense with "si" (si + present, future tense).
When we report what someone has said, there is a natural sequence of tenses. Reporting this sort of sentence using the present and the future means that we have to change the tenses to the imperfect and then the conditional, so:
Direct speech:

Si la riegas y crece como una planta, tendrás un perro".
If you water it and it grows as a plant, you will have a dog.

Indirect/reported speech:

Me dijo que si la regaba y crecía como una planta, tendría un perro.
She told me that if I watered it and if it grew as a plant, [then] I would have a dog.

We only have a bit of information on Indirect speech but we're planning to extend this content soon. 
I hope this clarified it.
Saludos
Inma