Growing zucchini vertically provides the advantages of saving space and making it easier to harvest. It can also decrease the risk of disease. And, it’s fairly simple to do if you have the right materials.
Here is a guide to growing zucchini vertically:
- Start planting in spring after all frost has passed.
- Find a spot that can provide your zucchini full sun.
- Test the soil for pH and nutrients.
- Apply appropriate fertilizer.
- Prepare well-draining soil with good moisture retention.
- Keep the soil moist but not water-logged.
- Set up the stakes for the plant to grow vertically.
- Tie and secure the stem in place with jute twine or VELCRO.
- Adjust or tie more jute twine as the stem grows.
- Watch out for pests and diseases.
- Prune your zucchini plant regularly.
- Harvest fully grown zucchini fruits.
Read on to learn more about some efficient and safe ways to grow zucchini vertically! This article will take you through the vertical planting process from start to finish.
1. Start Planting in Spring After All Frost Has Passed
Like many squash variants and cultivars, zucchini doesn’t grow well—if at all—in a cold environment. The vegetable prefers warm temperatures and produces fleshy fruits when the environment is suitable. Therefore, you have to wait until all frost has passed before sowing your zucchini seeds.
Check the soil temperature before planting. Ideally, it should be at least 70 °F (21 °C). Otherwise, the seeds will not sprout, or the seedlings will not grow well enough to bear fruits.
In some areas in the US, early spring temperatures could still fluctuate below 60 to 70 °F (15.6 to 21 °C), so it is best to start planting zucchini in mid or late spring when the temperatures remain well above that range.
Some people try growing seedlings indoors and wait until the outdoor soil temperature becomes warm enough before transplanting. This method is okay but requires extra steps of acclimatizing your plant to the amount of sunlight outdoors before you can safely transplant them into the ground.
It only takes approximately 2 months for zucchini to grow well enough to produce edible fruits. You can expect a good harvest by mid to late summer. It is best to plant seedlings in two to three batches one to two weeks apart for continuous harvest until late summer.
The plant stops producing quality fruits and cannot survive when temperatures drop in the fall.
2. Find a Spot That Can Provide Your Zucchini Full Sun
Zucchinis are sun-loving plants that grow best under 8 full hours of sun from 8 AM to 4 PM every day. They can benefit most from a spot that receives bright morning sunlight, meaning you must sow the seeds in an east-facing garden.
When growing the seedlings in pots indoors in preparation for warmer temperatures, be sure to allow the young plant to adjust to the outdoor sunlight and temperature before transplanting it to your garden soil.
Allow the plant around one hour of direct morning sun for around two days and gradually increase the number of hours by one each succeeding day. After a week or two, when the soil temperature reaches optimum levels (over 70 °F/21.11 °C), you can transplant the zucchini seedling into the ground.
3. Test the Soil for pH and Nutrients
Before transplanting zucchini seedlings or sowing seeds into the ground, be sure to check the soil’s pH and nutrient availability. This vegetable thrives well in mildly acidic to alkaline soil with levels ranging from 6.0 to 7.5.
Zucchini also grows well in soil rich in organic matter with good nitrogen levels and moderate amounts of phosphorus and potassium. You can have your soil samples tested in a laboratory to check for available nutrients.
When doing a laboratory check of your soil samples, you may also find signs of harmful microbes in the soil that you must address before growing your plants. If the ground contains only beneficial microbes, there is no need to eliminate them.
However, if it does, be sure to mend the soil and get rid of unwanted microbes like bacteria, fungi, and viruses that can infect your plant. There may also be other harmful pests or animals that you must eliminate first.
Meanwhile, if some essential nutrients are lacking, you can supplement the soil with organic compost or other amendments before sowing the seeds.
4. Apply Appropriate Fertilizer
Suppose your laboratory test results for soil samples return and show a shortage of essential nutrients like nitrogen, phosphorus, and potassium. In that case, you can use a nitrogen-rich fertilizer (10-3-3) for young seedlings. You may also use a balanced fertilizer with a 10-10-10 NPK ratio.
Often, adding organic compost into the soil should suffice. However, if the shortage is pretty severe, you will need to add fertilizers to the soil before sowing your seeds or transplanting the seedlings. Be sure to follow the recommended procedures and dosages indicated on the label when applying fertilizers.
Since zucchini is a fleshy fruit-bearing vegetable, it will eventually need a good amount of phosphorus. This nutrient is generally present in soil rich in organic matter. However, if the soil acidity becomes too low (below 6.0), the plant may not be able to absorb phosphorus.
When the plant starts sprawling, you may apply a phosphorus-rich fertilizer that works for garden vegetables.
Since you are growing the zucchini vertically, you will most likely use a smaller garden area. Be sure to calculate and adjust the amount of fertilizer necessary per square foot of garden soil.
5. Prepare Well-Draining Soil With Good Moisture Retention
Sandy loam works best for zucchini as it can provide good drainage while offering good moisture retention. In addition, you can amend the soil with compost to boost the amount of organic matter that can help provide essential minerals to the plants.
As discussed, zucchini seeds and seedlings prefer warm soil. If the temperatures fluctuate and go below 60 °F (15.6 °C), you can add peat moss to the ground surface. Doing so provides insulation, moisture retention, and mild acidity, which are all beneficial for your zucchini.
Some farmers who want to start growing zucchini early in spring keep the soil warm by adding black plastic mulch. It can also help with moisture retention. This method helps until the season’s temperature becomes steadily warm.
You also have to consider the space. When growing zucchinis horizontally, you must ideally leave 2 to 3 feet (60 – 90 cm) of space between seedlings. However, since you are going to grow them vertically, 1 to 2 feet (30 – 60 cm) of space would suffice.
It would be best to let the zucchini grow or spread enough before you can train them to grow upwards along with the stakes or trellis.
6. Keep the Soil Moist but Not Water-Logged
When exposed to cold and water-logged conditions, zucchini seeds may rot and fail to germinate. That is why it is essential to use warm, well-draining soil.
On the other hand, the soil may dry more quickly since the plant grows best under bright and direct sunlight for around 8 hours a day. Therefore, you need a well-balanced substrate that can provide excellent moisture retention without drowning the plant’s roots.
For loamy soil, water thoroughly at least once a week. The plant’s long taproot system will try to access moisture from deep into the ground.
Meanwhile, a sandy substrate requires less water but more frequent watering. Later in the season, as temperatures get warmer, you will need to water the plant more often.
Some gardeners would sometimes dig into the soil to know when to water the plants. If around 2 inches (5 cm) of the upper layer appears dry, it is time to add some water into the soil. You can add enough water to moisten only the dry upper layer, or water thoroughly if you trust your soil’s drainage capacity.
You may also use a moisture meter as a guide to decide when to water your plants. Be sure to keep the moisture level around 6 (in the middle) to keep your zucchini in the best condition.
7. Set up the Stakes for the Plant to Grow Vertically
Unlike other vining plants, zucchini doesn’t have roots or strong tendrils along the stems that help it climb. Instead, it has tiny and weak tendrils and grows on a single stem with branches sprawling in all directions, making it prone to dirt, diseases, and rotting. It also takes up plenty of space in your garden.
Growing the plant vertically helps get rid of or reduce these problems. However, you will have to guide and train the plant to grow upwards manually.
To do so, you will need to set up spikes or a trellis where you can attach the plant.
Stake
If you plan to grow only one zucchini plant in a pot or on your garden soil, a bamboo or metal stake should be enough. Ideally, it must be around 6 feet (1.8 m) long. Also, it helps to remember that when using a metal stake, make sure it is coated to prevent rust buildup.
Bury roughly one foot (30.48 cm) of the stake into the ground to ensure that it is stable enough to hold the zucchini as it grows upward. Secure the stake 3 inches (7.5 cm) away from the base of the seedling. Installing it early on will help prevent the risk of damaging the root system.
If your zucchini is in a pot, be sure that it is deep enough for the taproot system and the stake. I recommend using a pot at least 12 inches (30 cm) deep and around 24 inches (60 cm) wide. This size is good enough to hold the weight of the growing plant and its fruits.
Trellis or Cattle Panel
A wooden trellis or a metal cattle panel has better chances of holding the weight of the plant when it starts bearing fruits. Note that each zucchini fruit can weigh around 0.7 pounds (300 grams).
In addition, the stem of a zucchini plant tends to grow in a snake-like pattern, so it may be pretty challenging to tie them along the length of an upright metal stake. A cattle panel can also hold multiple zucchini plants up along its length.
See the following video for more on how to use a cattle panel:
When growing multiple zucchini plants in a row on your garden bed, you can set up a trellis or a cattle panel around 3 to 4 inches (7.5 to 10 cm) away from the plants. Secure both ends of the panel with metal stakes buried at least 1 foot (30.48 cm) into the ground.
Leave around 6 inches (15 cm) of space between the stakes at the far ends and the zucchini plants to be tied to the panel. For instance, if you are planting two zucchini plants 2 feet (60 cm) apart from each other, your metal stakes must be at least 3 feet (90 cm) apart.
The panel or trellis must also be at least 3 feet (90 cm) long, with both ends firmly attached to the stakes. They should be around 4 to 5 feet (1.2 to 1.5 m) high. It is important to remember that the panel and the stakes must not block the sunlight for your zucchinis.
8. Tie and Secure the Stem in Place With Jute Twine or VELCRO
When the main stem of the zucchini reaches about 8 inches (20 cm) long, you can start tying it up along the stake or the cattle panel. Before doing so, though, you have to cut off unruly leaves to expose the stem.
Use a sterilized knife or pruning shears and cut the leaf stalks an inch (2.5 cm) from the main stem. Ensure that the tools are sterile to avoid contaminating your plant with unwanted bacteria, viruses, or fungi.
Don’t worry about cutting off several leaf stalks because zucchini is pretty sturdy and can grow more leaves eventually. However, avoid cutting off young leaf growths and flower buds along the tip of the plant.
Use jute twine to tie the stem against the stake or panel. Do not tie it too tightly and leave enough space to insert a finger between the stake and the stem. Instead, tie more jute twines every 2 inches (5 cm) going up.
Jute twines are highly recommended because they are biodegradable. However, some people find it troublesome to tie it around the stem. A thin string may also snap at the weight of the plant while you are still training it to grow upwards.
You may also use garden tape to secure your plant’s stem for more convenience. It’s easy to use and provides a great grip to keep your plant in place.
9. Adjust or Tie More Jute Twine as the Stem Grows
Eventually, your zucchini plant will grow vertically and as it does, you should keep adding more jute twines or VELCRO tape every 2 to 3 inches (5 – 7.5 cm). Doing so will ensure that the plant will not droop at the weight of the fruits later on.
When using jute twines, regularly check for signs of weakness as the jute may snap as the plant gets bigger and heavier. Reinforce or replace the weak areas with new twines. You may also check your gardening VELCRO for any signs of weakness and reinforce when necessary.
10. Watch Out for Pests and Diseases
As mentioned, growing zucchini vertically reduces problems with diseases as they become more manageable. Pests may also have difficulty surviving because they will be easier to find and eliminate.
Here are some common problems for zucchini plants and how to deal with them:
Powdery Mildew
Zucchini plants sprawl naturally on the ground, forming a thick canopy of leaves that make it challenging to spot powdery mildew immediately.
The condition gets worse and spreads faster when plants are crowded. In addition, the fungi thrive best in warm weather, which is the most suitable growing season for zucchini. Growing zucchini vertically reduces overcrowding and makes affected leaves more visible.
Fortunately, it is easy to deal with powdery mildew using home remedies.
Some ways to manage powdery mildew include:
- Cutting off affected leaves, stalks, and fruit
- Burning infected parts
- Spraying a mixture of baking soda and neem oil on the infected plants
Pests
Various types of pests feed on zucchini’s fleshy fruits and broad leaves. Severe infestations can pose some serious problems to your harvest. However, most of them are manageable.
Here are some common zucchini pests to watch out for:
- Aphids
- Squash bugs
- Squash vine borers
- Cucumber beetles
You can manage these pests through the following ways:
Yellow Sticky Traps
Place yellow sticky traps on the cattle panel to catch bugs. Most bugs will stick to the trap and die, significantly reducing the number of pests. You may also place the trap on the ground and give the plant a little shake so that the bugs will fall into it.
Homemade Insecticidal Spray
You can also use a homemade insecticidal spray. Mix 34 oz. (1 liter) water, 0.03 oz. (10 mL) liquid dish soap, and 0.07 oz. (20 mL) neem oil. Place the liquid solution in a spray bottle and spray the plant in the evening to avoid leaf burn. It is effective against aphids.
Hand Removal
Alternatively, you could remove visible bugs and aphids by hand. You can also spray them away with water or wipe them off with cloth coated in one tablespoon of neem oil. Apply neem oil only at night to avoid killing off beneficial insects.
Zucchini Yellow Mosaic Virus
The Zucchini Yellow Mosaic Virus (ZYMV) is one of the worst diseases your zucchini can encounter. It is transmitted to neighboring plants through aphids. And once infected, the plants become unproductive, resulting in significant losses.
Symptoms of the infection include:
- Distorted leaves with dark green blisters
- Stunted plant growth
- Deformed fruits
Unfortunately, you cannot treat infected plants anymore. Since aphids are the vectors of the virus, you will have to eliminate them before destroying the plants so that they cannot carry the virus to other vegetation.
It is best to burn the sick plants and have the soil and neighboring plants tested as well. This method is necessary to ensure that the next batch of zucchini will be safe from the virus.
11. Prune Your Zucchini Plant Regularly
As mentioned, zucchini plants are pretty sturdy and can survive regular pruning. The leaves can grow too big and wide, making the plant heavier and more attractive to pests. Cutting the leaves next to the fruits can also encourage the plant to focus more on fruit growth than leaf growth.
When pruning your zucchini, start from the bottom. It will help the plant focus on growing more leaves on top to reach for more sunlight. It would help if you also cut off leaves infected with powdery mildew or those that show blisters.
Burn the infected leaves that you cut off from the plant. Do not think of adding them into your compost pile because there is no guarantee that the decomposition process in the pile can get rid of or neutralize the diseases.
It may be troublesome, but it helps to clean the tools before moving on to the next plant. Always use sterile knives or garden shears to ensure that you are not spreading any diseases.
12. Harvest Fully Grown Zucchini Fruits
Zucchini plants are very productive under optimum conditions. Vertically grown zucchini makes it easier to spot and harvest fruits. Be sure to cut off fully grown ones to prevent pests from damaging them before you can eat them.
You will know when to pick zucchini fruits based on their size. By the time they reach between 6 and 8 inches (15 – 20 cm), they should be ready for harvest. Any bigger, and they would be too ripe, rotting, and attractive to more pests.
Harvesting fruits frequently can also help lighten the load of the plant and prevent your stake, trellis, or cattle panel from falling over. In addition, removing fully grown fruits can encourage the plant to produce new ones.
Final Thoughts
While growing zucchini vertically requires more work, the benefits you can get from doing so outweigh the trouble.
Here are some benefits that can help you decide that this method of growing zucchini is worth it:
- It saves space.
- It can reduce the problem with pests, dirt, and diseases.
- It can prevent the fruit from rotting under thick and moist leaves.
- It is easier to harvest.
If you find the advantages listed above convincing, try growing your zucchini vertically next spring! Just follow the guidelines I shared.
