If your soil pH is too low or too high, you may need to amend it. If the pH is too low, you can raise it by adding some lime. If it’s too high, you can add some sulfur. Amending your soil’s pH can take several months, so plan ahead and test your soil well before you plant your beans. Since it’s so difficult to change the pH of your soil, you might consider growing your beans in a raised bed if your soil isn’t right. Alternatively, you could grown a different bean.
Since it’s a vegetable, giving black bean plants too much nitrogen can cause your plants to produce lots of leaves and only a few beans.
Your soil temperature should reach at least 60 °F (16 °C) before planting. Your beans should germinate in 10-14 days, and will reach maturity in about 100 days. [5] X Research source Try to plant the beans at a time when you know they will get at least 3 months of reliably warm weather. [6] X Research source
You can use mycorrhizal fungi as an inoculate to help the roots form and to help the plant with nitrogen fixation. You can apply some inoculants by pouring the beans into a bag with the inoculant and shaking gently to coat the beans. Others must be mixed into the soil before planting. Follow the directions on the product package.
Give your beans a little extra space (at least 6 inches or 15 cm) between each plant if they are a bush variety as opposed to a vining variety. Sow your beans with the eyes facing down. [9] X Research source
Take care not to over-water your beans. Black beans will start to rot at the roots if they sit in soggy soil too long. [12] X Research source
Mulch your beans about 2-3 weeks after planting, or once the plants have sprouted and grown a couple of leaves. [15] X Research source Leave 1-2 inches (2. 5-5 cm) of mulch-free space around the stem of each plant. Having mulch up against the stems may cause the plants to rot.
Each trellis or pole should be about 3 feet (. 9 m) high.
If you’d rather not use chemical pesticides, try introducing some ladybugs to your garden. Ladybugs will eat aphids and other pest insects. You may be able to purchase ladybugs at your local garden center.
Black beans generally reach maturity and are ready for harvest 90-140 days after planting. If your black bean plant is a bush variety, all the pods should mature at the same time. If you have a vining variety, you will need to harvest the pods regularly throughout the growing season to encourage continued production.
You can harvest immature or fresh beans before they are fully dry, but you can’t store them for as long. Try to harvest your beans during dry weather. If your beans are almost ready to harvest but the forecast calls for a lot of rain, bring the whole plant indoors and hang it upside-down so it can finish drying inside. [21] X Research source
Hand-shelling black beans can be tedious work. You may find it easiest to collect the beans if you put all the pods in a sack or pillowcase and stomp on it or hit it against a wall a few times. [22] X Research source
