If you've decided you want to grow crops in Stardew Valley, then you're going to have to buy some seeds. Now you have two locations you can visit to buy seeds from, that is JojaMart and Pierre's General store. For now we'll treat it as if you were going to Pierre's. Here are a few selections of the items on offer.
Parsnip are the cheapest and quickest to grow seeds taking only 4 days to mature and costing 20 gold.
The Bean starter takes 10 days to mature and you can keep harvesting crops without having to plant it again. It takes 10 days to grow and because it grows on a trellis will be a physical barrier to you, so be careful when placing it do as to not block anything off.
The Potato only takes 6 days to grow and can be continually harvested like the bean plant but it won't cause an obstruction because it doesn't grow on a trellis. The seeds cost 50 gold.
Jazz seeds produce a flower in 7 days and will stay in bloom until the season is over. They cost 30 gold each.
Basic fertiliser slightly increases the chance the crop you are growing will be of higher quality, but costs a whopping 100 gold.
Once you've chosen the seeds you want you'll need to till the soil (dig a hole).
Then we put in our seeds.
And finally we water the crop.
Some crops are asked for in later quests and events, so make sure you have some saved in a chest.
If you put down a fertiliser before you plant a seed you have an improved chance the crop will be of higher quality.
Flowers in bloom around bee hives cause the honey they produce to be flower honey, which is worth more than the standard wild honey produced.
Make sure to harvest crops and flowers before the season ends as they will die and you will lose out (there are exceptions, so read the descriptions).
Be mindful where you place the starter beans as the trellis they grow on form a barrier and can obstruct your movement.
Make sure you have enough stamina to plant crops by only tilling the amount of soil you need and remember to leave enough energy so you can water them too.
Remember to water your crops everyday, unless it rains, in which case mother nature is taking care of business.
What do you want to do next?