La luz solar directa llega a la jardinera.

Because llegar often means to arrive or to reach, and when it indicates a destination, it usually takes a.

So:

• llega a la jardinera = reaches the planter
• literally, something like arrives at the planter

This is normal Spanish structure:

• El tren llega a la estación.
• La carta llegó a mi casa.
• La luz llega a la ventana.

So the a is not optional here.

In this sentence, jardinera most naturally means a planter, flower box, or plant box.

Depending on the country or context, jardinera can have other meanings too, but in a sentence about sunlight, the most likely meaning is a container where plants grow.

So a learner should understand it as something like:

• planter
• window box
• planting box

Yes. Jardinera is a feminine singular noun, so it takes the feminine article la.

• el jardinero = the male gardener
• la jardinera = the female gardener / the planter

Here, the meaning is planter, and the grammatical gender is still feminine.

That is why the sentence says:

• a la jardinera

not:

• a el jardinera
• a la jardinero

Spanish adjective order is often different from English. Here, the most natural order is:

• luz = light
• solar = solar / from the sun
• directa = direct

So la luz solar directa means direct sunlight.

A useful way to think about it is:

• luz solar = sunlight
• luz solar directa = direct sunlight

The adjective solar stays close to luz because it classifies the type of light, and directa adds another description.

Spanish adjective order is not always a simple mirror of English, so this phrasing is something worth learning as a chunk.

Because it describes luz, and luz is a feminine singular noun.

Adjectives in Spanish usually agree with the noun they describe in gender and number.

So:

• la luz directa
• la luz solar directa

If the noun were masculine, the adjective would usually be masculine:

• el calor directo

If it were plural:

• las luces directas

So directa is feminine singular to match luz.

Because luz solar specifically means sunlight or solar light, not just the sun itself.

Compare:

• el sol = the sun
• la luz solar = sunlight

Spanish can also say la luz del sol, which is very natural too. But luz solar is a common and slightly more compact way to say it.

So:

• la luz solar directa = direct sunlight
• la luz directa del sol = direct light from the sun

Both are understandable, but luz solar directa is a neat, standard phrasing.

No. Llegar often means to arrive, but it can also mean to reach, to get to, or to extend to, depending on context.

With physical things like light, sound, water, or smell, llegar a often means to reach.

For example:

• El sonido llega hasta aquí. = The sound reaches here.
• El olor llega a la cocina. = The smell reaches the kitchen.
• La luz llega a la jardinera. = The light reaches the planter.

So in this sentence, llega is not about a person arriving somewhere. It is about sunlight extending to or reaching a place.

Yes, absolutely. That is a very natural alternative.

• La luz solar directa llega a la jardinera.
• La jardinera recibe luz solar directa.

Both are correct, but they focus on slightly different things:

• llega a la jardinera focuses on the sunlight and where it reaches
• recibe luz solar directa focuses on the planter and what it receives

In everyday speech, both would sound natural.

In a full normal sentence like this, yes, la is the natural choice.

• La luz solar directa llega a la jardinera.

Spanish often uses the definite article more than English does, especially when talking about something in a general or identifiable way.

Without the article:

• Luz solar directa llega a la jardinera

this sounds incomplete or unnatural in ordinary Spanish.

So even though English might sometimes just say Direct sunlight reaches the planter, Spanish normally uses La here.

Because the sentence is stating a present fact or general condition.

• llega = it reaches / arrives

Spanish often uses the present tense for general truths, repeated situations, or descriptions:

• El sol sale por el este.
• La lluvia entra por la ventana.
• La luz solar directa llega a la jardinera.

So this can mean something like:

• direct sunlight reaches the planter
• the planter gets direct sunlight

It does not have to mean it is happening only right this second; it can describe a usual condition too.

No. Al is the contraction of a + el only.

• a + el = al
• a + la = a la

So:

• llega al jardín = reaches the garden
• llega a la jardinera = reaches the planter

Since jardinera is feminine and uses la, there is no contraction.