Those who live in an apartment or home with little to no backyard might have a hard time finding gardening space outside. Luckily for you, some plants, such as grapes, can grow well inside if you take the steps needed to allow them to thrive.
So, how do you grow grapes indoors? Follow these steps to successfully grow grapes inside your home, office, or other indoor space:
- Select a grapevine that grows well indoors.
- Choose and prepare the right sized container or planting pot.
- Purchase a soil that grapes grow well in.
- Understand how to plant the grapes.
- Place your grapes by a window with adequate sunlight.
- Water and fertilize your growing grapes.
- Prune the grapes annually, or as needed.
If you are looking to plant your own grapes without the variables of outside gardening, this article will discuss everything you need to know about growing grapevines indoors.
Select a Grape Vine that Grows Well Indoors
Although grapes tend to do their best outdoors in the United States, specific varieties of grapes will grow well in warm climates and thrive inside. It is ideal to have a greenhouse or very warm and sunny room, but keeping grapes in front of a window that gets lots of sunlight can do the trick. The Muscat of Alexandria and the Black Hamburg are two types of dessert grapes that will grow well indoors.
The warm inside temperature will help grapes grown indoors ripen and become sweet. Grapes vines expand as they grow, so looking for plants that produce their fruit close to the trunk are also good options. Some of the varieties that are more suitable for growing in a pot include:
- Swenson Red
- Early Muscat
Choose and Prepare the Right Sized Container or Planting Pot
You will need to select a large and sturdy container to grow grapes in.
Here are some characteristics to look for:
- 15-20 gallon pot
- 18-24 inches wide
- 16-18 inches deep
- A pot with drainage holes
- Heavy Duty material to prevent cracking such as (available from Amazon):
Grape roots can spread up to eight to ten feet, so you will need to have a pot big enough for the roots to grow in. Ceramic or wood pots will hold up better than plastic, which may crack over time. Make sure each container has proper drainage, so the grape roots aren’t always sitting in wet soil. You can help with drainage by adding a layer of pebbles or rocks at the bottom of the pot before adding the soil.
Selecting the Best Soil for Grapes
There are several characteristics to look for in soil when picking one to use for growing grapes. Here are some steps to take when selecting the proper soil:
- You will want to make sure your soil has a pH of 5.5 to 7.0. The pH of the soil can be verified with a soil testing kit.
- Find a soil, such as sandy loam, that contains the right amount of nutrients. Other soils to consider might be silt loam or clay loam such as (available from Amazon):
- Make sure your soil drains properly. This can be tested by digging a 12-inch hole and filling it with water. An hour later, fill the hole again with water and then time how long it takes to drain. If the hole drains within several hours, then the soil is too dry. It should hold water for almost 24 hours to support grape growth.
- Improve the soil as needed. Adding organic matter to the soil can help the growth of grape plants, just make sure the right nutrients are added to the correct type of soil. In this case, you can usually follow the manufacturing instructions on the bag of fertilizer you choose. Here are some excellent options (available from Amazon):
- Mulch. Adding a layer of mulch on top of your soil can be very beneficial. A top layer of mulch helps keep more moisture in the soil and can protect the roots from dramatic changes in temperature. Here are some types of mulch you could use (see on Amazon):
Understand How to Plant the Grapes
You’ve chosen your grapevine, found a suitable container and spot, and have the soil and fertilizer. Now, the next step is to plant your seeds.
Here is a step by step process to follow:
- Place your pot on something sturdy with wheels. As the plant grows heavy, this will make it easier to move.
- Line the bottom inch of your pot with rocks, gravel, mulch, or any material that will allow for proper drainage.
- Mix your potting soil and fertilizer, using the recommended ratios listed on the fertilizer bag.
- Fill the pot about halfway full with your soil and fertilizer mix.
- If using a grapevine, remove it carefully from its container and gently break up the soil to loosen the roots.
- Place the vine in the center of your pot, allowing the roots to touch the top of the soil.
- Fill in the remaining soil around the roots until it reaches 1 inch below the pot. Gently press on the soil to remove any air pockets.
- Insert a trellis close to the grape plant, pushing it to the bottom of the pot.
- Secure the plant to the trellis to guide the grapevine up it as it grows. Due to the length that vines grow, they need to have a support system, or trellis, to grow up and along. As the plant grows, you will need to help guide it along the trellis.
- Place the plant in sunlight and water it.
If you choose to grow your grapes from seeds, you will need to start your growing process months in advance. If you plan on moving your seeds outdoors, start the growing process during the winter months. There are a few extra steps you will need to follow before you switch your plant over to a larger pot.
- Pick out the seed variety you want to use.
- Rinse the seeds off.
- Soak the seeds for 24 hours in distilled water.
- Chill your seeds to replicate their dormant phase during winter.
- Fill a bag with wet paper towels, damp sand, or peat moss and place the seeds inside.
- Cover them with a growing medium then place them in the refrigerator for 2 to 3 months.
- In early spring, plant the seeds in small pots filled with soil.
- Adjust the temperature of the seed according to the time of day. You will want a minimum of 70 degrees Fahrenheit during the day and around 60 degrees Fahrenheit at night. Keep the soil moist but avoid overwatering.
- When the seeds have grown 3 to 4 inches, transplant them to a slightly larger pot. Continue the temperature and watering routine.
- When the plant is one foot tall, it may be transplanted to its final pot. Prepare this pot according to the steps above for planting grapevines.
Place Your Grapes by a Window with Adequate Sunlight
For grapes to grow inside, they will need at least 6 to 7 hours of sunlight each day. It is essential to find a sunny window or room to grow the grapes in. A sunroom is preferred; however, south-facing windows can get an adequate amount of light and warmth to allow vines to grow.
Here are a few other things to consider that will help your grapes produce indoors:
- Good air circulation. You can open a window throughout the day or have a gentle fan blowing on them. Strong winds or breezes can inhibit growth and damage the plant.
- Warm room temperature. Grapes grow best in a warm climate, so keep the temperature above 60 degrees Fahrenheit. In the winter, the temperature can be kept slightly cooler.
- Provide a trellis for the vine to grow up. Grapevines get very long as they grow and will need support from a trellis. Insert one or two into the pot to provide them something to grow on. It is crucial to make sure you have enough space indoors to allow your grapevine to grow to its full potential.
Water and Fertilize Your Growing Grapes
Grapes will produce more fruit and grow better when they are well-nourished. Use the table below to determine when to fertilize and water your vines.
|Early Spring(just before the growing season)||Start watering once seeds are planted.||For your first fertilization, select a fertilizer that has nitrogen to help start the growing process.|
|Spring(when growth starts until flower buds appear)||Water every 2 to 3 days. Keep the soil moist, adding enough water to wet the soil about 10 inches deep.||Fertilize every three weeks using a fertilizer that is high in potassium and phosphorus.|
|Summer(when flowers and lots of leaves appear)||Water every 2 to 3 days. If the soil about 1 inch deep feels dry, then water the plant.||Fertilize once a week with a fertilizer that is high in potassium and phosphorus.|
|Summer(as grapes grow and ripen)||Water every 2 to 3 days. Avoid overwatering the plant as this may rot the roots and kill the plant.||Stop fertilization as the fruit ripens to allow the produce to sweeten.|
|Winter(dormant season)||Cut back on watering.||No fertilization is needed.|
After your first dormant season, you will not need to fertilize the grapes again with a nitrogen-containing fertilizer, instead, find one that is low in nitrogen but still high in potassium and phosphorus. Keep in mind that fertilization is not necessary for grapes, but will only improve the production results. You will also want to make sure you avoid over-fertilizing your grapes. This can cause the grapevine to grow too rapidly and not produce any fruit.
Pruning Your Grapes
During the beginning growing season, you will trim small branches off of your grapevine. Although this will produce fewer grapes, the ones that do develop will be larger and more flavorful. As the branches grow more prominent, you can do a second trimming to thin them out a little more.
At the end of the growing season, grapes need to be pruned to prepare them for next spring. Pruning typically takes place in January and February. Keep in mind as you prune, you will be removing almost all of the wood growth to allow for better quality grapes next season. Any growth that is more than two years old won’t produce much more fruit and can be pruned away as well.
When you prune, you will remove all of the growth except for two buds, or offshoots from the trunk of the plant. Select branches to keep that will grow towards the trellis in the year to come.
When to Harvest Grapes
Once you have correctly pruned and pollinated your vine and grapes are beginning to grow, you might wonder whether or not they are ready to pick. The ideal time to harvest grapes is between September and October; however, there are a few signs you can look for to determine if your grapes are ready.
- If the grapes feel soft and juicy to the touch, then they are ready to pick.
- You can also look at the seeds inside the grapes to determine if they are ready. Seeds will turn from white to brown when the grape is ready to be harvested.
- Taste the grapes. If they taste sweet or you like how they taste, then go ahead and harvest them.
Storing Freshly Harvested Grapes
Once you have harvested your grapes, you will want to store them properly if you aren’t planning on eating them right away. Grapes can be stored in a sealed container and refrigerated for up to 3 weeks. When saving grapes, do not wash them. The added moisture will cause the grapes to ripen and shorten their shelf life.
Grapes can also be frozen and saved for later use. Here are some steps to follow when freezing grapes:
- When freezing grapes, you will want to spread them out on a baking sheet or pan that is lined with wax paper. This will prevent the grapes from freezing to each other or the pan.
- Once frozen, the grapes can be placed in a freezer bag or container and put back in the freezer until they are ready to be used.
Frozen grapes can be eaten for a snack, thawed for a couple of minutes, and then consumed or used in smoothies, desserts, and other recipes. When freezing grapes, you will want to use them within one year for best quality. It is not recommended that grapes, once thawed, are refrozen.
Another method for storing grapes is dehydrating them. This process takes about 24 to 48 hours, depending on what dehydrator you use. Dehydrated grapes are known as raisins. They make a great snack and are also used in baking and other recipes. When done correctly, dehydrated grapes can last up to 5 years.
Here are the steps for dehydrating grapes:
- Wash the grapes to remove all dirt, bugs, or anything else found on the grapes.
- Remove any seeds the grapes might have by cutting them in half and scooping them out.
- Spread out the grapes on the dehydrator trays.
- Set the dehydrator to its fruit setting, about 135 degrees Fahrenheit.
- The dehydrator will run for about 24-48 hours, but you can test your raisins as they dry to make sure you get them to the level of dryness that you like.
If you need a dehydrator, here are a few recommended ones (see on Amazon):
- Excalibur Electric 9-Tray Food Dehydrator
- Hamilton Beach Digital Food Dehydrator, 5 Tray
- Presto Dehydro Electric Food Dehydrator
Can I Grow Grapes from Store-Bought Grapes?
There are two different ways you can attempt to grow grapes from ones purchased at the store. Use this chart to guide you in the process:
|Growing From Store Bought Grape Seeds||Growing From Store Bought Grape Vines|
|1. Select a type of grape to purchase from the grocery store. Keep in mind that genetics from that variety might not fully transfer over to the grapes you grow.||1. Buy grapes that are on a healthy-looking vine that is at least 4 inches long.|
|2. Remove a handful of seeds from the grapes you have purchased because a tiny percentage will germinate.||2. Remove the grapes from the vine.|
|3. You will need to put your grape seeds through the cold treatment process listed under “Understand How to Plant Grapes.”||3. Cut off any brown, black, or red parts of the vine. If the vine is withered, then pick a different one.|
|4. After refrigerating the seeds for several months, place them in a small pot, and keep them at room temperature.||4. Place the vine in a plastic cup full of water for four days to allow roots to grow.|
|5. Water the seeds every few days to keep the soil moist, but not soaked.||5. Once roots have grown, transfer the vine to a small pot filled with soil.|
|6. Once seeds start to sprout and grow, transfer them into larger pots as needed.||6. Keep the soil moist by watering the vine and place it in a sunny spot.|
|7. Continue watering the plants and exposing them to adequate amounts of sunlight, following the other steps listed in this article.||7. As the vine grows, transfer it to larger pots filled with nutrient-rich soil. Keep watering the vine and exposing it to sunlight, following the other steps listed in this article.|
How Long Does it Take Grapes to Grow from Cuttings?
Unlike other plants, grapes are not usually grown from seeds. Farmers who grow grapes will use the cuttings from the grape plant they want to grow. Doing this is a better guarantee of carrying over the characteristics of the type of grape plant you wish to produce.
If you start with seeds from a green grape, there is a very good chance you will end up with red or purple grapes. All the characteristics, including size, color, flavor, and density, will vary when you plant seeds instead of cuttings.
Growing grapes from cuttings will take about three years, sometimes four. Grapes need time to develop and strengthen their root system and vines. The number of grapes grown in the third year will be less than in the following years.
How Long Does it Take to Grow a Grape Vine from Seeds
Growing grapes is a slow process that requires lots of work, care, and patience before you typically yield results. If you choose to grow your grapes from seeds, you will need to start the growing process sooner than you would a cutting, and it can still take up to three years before any fruit is produced. After the fruit has started producing each season, you will typically see grapes appear each spring and continue growing well into summer.
How to Deal with Plant Fungus and Bacteria
Fungal diseases can be a common problem for grapevines. You will want to check your grapes frequently to make sure there are no signs of a fungal disease.
Here is what you should look for:
- Yellow spots on top of the grape leaves
- Off-white spots on the bottom of the leaves
- Fuzzy gray mold on the grapes
- Fruit that is rotting or splitting
- Purple or gray leaves
- Powdery substances on the stems, fruit, or leaves
If you come across a fungus problem on your leaves, there are a few steps you can take to treat it.
- In a spray bottle, mix 1/2 cup of whole milk with 4 ½ cups of water. Shake the mixture well and spray lightly on the entire grape plant twice a week to help control the fungus.
- Purchase an organic sulfur-based fungicide, such as Bonide Sulfur Plant Fungicide (see on Amazon), to treat any mildew by following the instructions on the package.
- For gray mold, cover the soil to prevent any mold from surviving inside the soil and spray the entire plant with a copper-based fungicide, such as Bonide Copper 4E Fungicide (see on Amazon), according to the packaging’s directions.
Bacterial infections can be spread to a grape plant in a variety of ways, such as by water, soil, debris, insects, and gardening tools. If your plant picks up a bacterial infection, you may find red spots, black spots, or black rotting fruit that will need to be treated right away.
To best identify and treat a bacterial infection, you can take an infected piece of your plant to a specialist for information on what to do. Usually, bacterial infections can be treated with pesticides and fungicides. When handled correctly, bacteria and fungus often won’t kill the entire grape plant.
How do I Help my Grapes Grow Best
In summary, here are the critical factors in helping grapes grow:
- Use fertilizer sparingly or according to package directions.
- Plant the vines in a large, sturdy pot, transferring to a larger container when needed.
- Provide a trellis for them to grow on.
- 6 to 7 hours of sunlight or LED lamp, minimum.
- Water frequently to keep the soil moist, but not soaked.
- Keep a layer of mulch on top of your soil.
- Prune as directed during the growing season and dormant season.
- Encourage pollination by slightly shaking the plant when flowers are present.
What to do If Grapes Aren’t Producing Fruit
When taken care of correctly, grapevines will typically improve production from season to season. If you have been growing your vine for over three years and aren’t seeing any fruit or the fruit has stopped producing, there are a few factors that could be causing this.
- Make sure that your plant is getting at least 7 hours of direct sunlight each day. If grapevines don’t get enough sunlight, then the flower buds won’t blossom correctly. If you find you need more sunlight, you can use an LED growing lamp.
- Go over how you are pruning the vines to make sure that it is done correctly. Over or under pruning can affect the blossoms and how much fruit is produced.
- Cut back on the amount of fertilizer you use to make sure you aren’t overloading the plant and causing fewer grapes to be produced.
- You can try to help the pollination process along by gently shaking the plant or placing a fan on it to encourage its pollination. In rare cases, you will get a vine that only has male or female flowers on it. If this occurs, you will need a second vine nearby to cross-pollinate with.
- Double-check that the plant has not been infected by fungus, bacteria, or other pests. Look for signs of disease and treat them accordingly.
Although grapes can be a challenge to grow, they can successfully be grown indoors when the proper steps are taken. This guide has provided you with a step by step process of what you need to know and do to find success.