cucumbers growing guide

Crisp, juicy, delicately flavored cucumbers are one of the joys of summertime. A chilled cucumber soup can cool you down on the muggiest summer evening and cucumbers make a delicious accompaniment to any lunch or dinner, just sliced and salted.

Cucumbers are ideal for the beginning gardener because with just a little work, a bumper crop of cukes is yours for the picking. Growing cucumbers in a Tower Garden is even easier than growing them in the ground. No kneeling, no bending, no tilling, no dirt! Of course, there are some tips and tricks you should know about for growing healthy, productive cucumber plants in a Tower Garden.

Read on to learn how to:

● Choose your cucumber varieties
● Sow seeds
● Transplant seedlings
● Pinch
● Fight pests
● Know when to harvest

You can also download this guide to keep it handy.

Before You Plant: Choosing Your Varieties

European Pickling
These are smaller cucumbers, perfect for pickling. You can grow them on a trellis or another supportive device next to your Tower. That way, the plant has its own place to grow and won’t dangle over the other crops on the Tower and block their light.

American Pickling
These varieties are thicker-skinned and also great for pickling. There are many varieties of American pickling cucumbers, and they come in all sizes. You’ll want to choose a variety with resistance to molds and mildews.

American Slicing
American slicing cucumbers are just right for salads and sandwiches. These are the standard long 7"–9" cucumber you see in grocery stores. If you live in a hot climate, you’re in luck: heat-tolerant varieties are available.

Seedless and Thin-Skinned
This is the best salad-quality cucumber you can grow. There’s no need to peel them—they’re never bitter, and they have crisp fruit and tender skin.

Specialty cucumbers come in unusual shapes and sizes, including the heirloom lemon cucumber that’s round, has a yellow skin and is about the size of, you guessed it, a lemon. These are something to talk about!

Before You Plant: Deciding When to Plant

Cucumbers grow vigorously under the right conditions. They love warm weather, and have an optimal growing temperature of 75–85° F. When the mercury hits the 90s and stays there, though, the plant will slow in its production of fruit, and some varieties will shut down and stop growing altogether. That’s why it’s important to choose the right variety (e.g., heat-resistant) if you’re growing outdoors in an area with hot summers. You may want to plant earlier in the season too.

Planting: Seed Sowing and Germination

Your Tower Garden comes with everything you need to get started growing cucumbers. Remember: the germination range for cucumbers is 65-70° F.

Step 1: Locate the slab of rockwool cubes and place in the seed starter tray.
Step 2:
Thoroughly wet the rockwool cubes by completely submerging the slab for 30 minutes in Tower Garden Mineral Blend nutrient solution. This will stabilize the pH of your cubes. After 30 minutes, thoroughly flush cubes with fresh water. Important: Because the rockwool repels water, you can’t get away with just spraying it. You really need to soak it!
Step 3:
Drain all excess water from the seed starter tray.
Step 4:
Sow 1 seed per cube.
Step 5:
Be sure the seed has good surface contact with the cube hole and lightly cover with coarse vermiculite up to the rockwool cube surface, which will help retain the right amount of moisture. Gently sprinkle a little water over each hole to wet the vermiculite.
Step 6:
After seeding, put a little water into the bottom of the container. If possible, use filtered water without chlorine. Do not close the lid.
Step 7:
Place seed starter tray outside in semi-shade (a bench or table will do nicely) until the seeds have germinated. Always keep about 1/8" to 1/4" of fresh water in the bottom of the tray.
Step 8:
Once the seeds have germinated (about 5–8 days or longer in cooler temperatures), IMMEDIATELY place outside in full sun for 7–14 days to increase their hardiness.
Step 9:
Make sure your sprouted seeds have 1/4" of fresh water in the bottom of the tray each morning so your seedlings won’t dry out during the day. Add Tower Garden fertilizer solution every other morning in place of fresh water.
Step 10:
Ten to 14 days after germination, and once the fear of frost has passed if you’re growing outdoors, your seedlings should be ready to transplant into the Tower Garden!

Planting: Transplanting into the Tower Garden

Transplant the seedling into your Tower Garden when there are 2–3 true leaves. This should happen 10–14 days after germination. The exact time frame depends on the date of the last frost in your area. You’ll know your plants are ready when they have a good root system growing from the rock fiber starter plugs.

If you’re growing outdoors and using a Submersible Heater and a frost blanket, you can start transplanting 3 weeks before the suggested planting date. Just make sure you heat the water in the Tower Garden Mineral Blend reservoir to a minimum of 70° F until daytime temperatures rise to that level.

Step 1: Gently separate the cubes from the rockwool slab. Do your best to break as few roots as possible.
Step 2:
Your assembled Tower Garden should already have a net pot in each planting port. Place each cube with its newly planted seedling into one of these net pots. Guide any hanging roots from the net pot into the growing pot.
Step 3:
Be SURE the bottom of the cube is secure against the bottom of the net pot. This aligns the plant for optimal irrigation inside the Tower Garden and keeps it from getting too dry.

Where you place your cucumbers within your Tower Garden will be important due to their vining nature. We suggest placing the plant(s) in the lower tier(s) of your Tower Garden. This will allow the vines to spill over onto the ground surface. You can also train the vines onto the support cage and let them fountain over the sides.

Just be aware that cucumber tendrils will wrap themselves around anything! Therefore, you may want to train the vines to grow along deck balustrades, fences or your Tower Garden cage. It’s easy to get semi-curled tendrils to attach to a surface—gently take the tendrils and begin wrapping them onto the desired surface. They will quickly establish a hold. Don’t be afraid to train the plant where you want it to grow!

Tower Garden Tip: Consider growing other plants with an upright growth pattern directly above your cucumbers. Since the cucumber tendrils will attach themselves to other plants, you don’t want another cascading plant directly above, as a cucumber vine can easily overgrow it.

Maintaining Plant Health: How to Keep Your Plants Happy

Tower Gardens are wonderfully free of some of the bothers of traditional gardening: there’s no weeding, tilling, kneeling, or getting dirty! Just a few basic maintenance steps will keep your plants healthy and happy.

Maintain Tower Garden Mineral Blend Levels

Because your Tower Garden doesn’t use any dirt, your plants are totally dependent on Tower Garden Mineral Blend to get their nutritional needs met.

● Maintain the recommended Mineral Blend levels at all times to allow your plants maximum uptake of the nutrients they need to grow.
● With a “young” Tower Garden, check the Mineral Blend levels twice a week to learn how quickly your plants are utilizing the tonic solution. Later, as your plants grow larger and the roots have reached the reservoir, you’ll probably need to refill the tonic solution every 2–3 days.

Avoid Plant Stress

It’s well documented that healthy plants are less desirable to insects! A plant that is stressed in some way—whether from lack of water or nutrients, or from heat, wind or cold stress—becomes an easy target for pests and disease.

Dehydration, starvation, heat, wind and cold can all cause a plant to wilt. Therefore, the #1 rule for keeping plants healthy is to prevent wilting!

● Always maintain a cool temperature within the reservoir. Tower Garden Mineral Blend should never feel warmer than the temperature of your skin.
● On very windy or extremely hot days if your Tower Garden is outside, turn the irrigation timer to run constantly for the most stressful hours of the day. Just remember to turn the timer back to its normal cycling times!

Tower Garden Tip: If your Tower Garden has to be partly shaded due to your surroundings, it is better to have afternoon shade when the day is the hottest!

Keep It Clean

When it comes to your Tower Garden, clean is good. You don’t have to pass the white-glove test, but keeping your Tower Garden debris free discourages plant pathogens.

● Keep your Tower Garden in as clean an area as possible.
● Remove most mature, yellowing or brittle leaves from the base of the plant.
● Keep loose plant debris and insect debris clear from the top of the reservoir tank, and place the compost of discarded plant clippings well away from your actively growing Tower Garden.

Maintaining Plant Health: Managing Pests

Like most crops, cucumbers are vulnerable to pests. These vary by region and time of year. Fortunately, growing plants off the ground in a Tower Garden is one of the best ways to avoid pests! Here are the most common pests affecting cucumbers:

Aphids are small, soft-bodied insects that are most commonly green and black in color, but may also be gray, brown, pink, red, yellow or lavender. They tend to feed on tender, young growth, causing it to appear puckered or deformed. Although they are visible to the naked eye, they also leave behind an excretion known as honeydew, which is another method of identification.

What to do if you have them: There are numerous methods of aphid control, including botanical sprays such as insecticidal soap, pyrethrum, rotenone and horticultural oils. Beneficial insects such as ladybugs will also help to eradicate the pest.

Cucumber Beetles
As you can guess from the name, cucumber beetles are a major cucumber pest, especially when the plants are young. Spotted, striped and banded cucumber beetles can be present during all stages of the plant’s development and during the entire growing season. The beetles feed on all parts of the plant, including the fruit and flowers. These pests also act as vectors for transmission of bacterial wilt.

What to do if you have them: You can control cucumber beetles by using botanical sprays such as pyrethrum, rotenone and insecticidal soap.

Spider Mites
Spider mites are a potential cucumber pest, especially in hot, dry conditions. These sapsuckers cause damage that appears as pale-yellow spots ranging in size from specks to large areas on the tops of the leaves. Spider mite damage can progress quickly and go unnoticed due to the insect’s small size. The insects can cause overall stunting of plant growth or even kill the plant.

What to do if you have them: You can control spider mites by using botanical sprays such as insecticidal soap and neem oil sprays. Beneficial insects such as ladybugs and minute pirate bugs will also help to eradicate the pest.

Maintaining Plant Health: Managing Disease

Not all plant problems are caused by pests; some are caused by disease. Here are the ones most likely to affect cucumbers:

Bacterial Wilt
A serious disease of cucumbers, bacterial wilt is transmitted by one of the major crop pests, the striped cucumber beetle. Seedlings and young plants are most susceptible. Symptoms of this disease appear first in individual leaves followed by the wilting of all the leaves on entire stems, culminating in the death of the whole plant. Infected plants should be removed immediately.

What to do if you have it: Minimize the risk of introducing this disease to your cucumbers by managing the cucumber beetle population. Purchase seed and plant varieties that have genetic resistance to bacterial wilt. Keep the area around the Tower Garden clean of plant debris.


A gray mold that thrives in humid yet relatively cool environments, botrytis is a devastating disease that can be exacerbated by poor air circulation. This gray-brown fuzzy growth can appear on plant debris that falls from the plant or on the remaining stem after harvest.

What to do if you have it: The best way to control for botrytis is to keep a clean growing environment.


Powdery Mildew
This is one of the most widespread and recognizable fungal diseases. Powdery mildew forms a white to grayish powdery growth, usually on the upper surfaces of leaves. Fungal spores are spread by wind and can survive the winter on nearby plants and plant debris. The warm days and cool nights of late summer create an ideal climate for spore growth and dispersal.

What to do if you have it: To control mildew, prune your plants to improve air circulation and dispose of infected plants. To control minor infestations, pick off affected plant parts and dispose of them immediately. In the case of a larger outbreak, apply bicarbonate and copper sprays to prevent spread of the infection.

For more info: For additional information on how to handle crop pests, consult your local office of the Cooperative Extension System, a nationwide, governmental educational network that provides useful information on agricultural practices.


When to replace your plants

If a plant has become too diseased despite control efforts, replace with new plants.


Pickling cucumbers do not need to be pruned. While not strictly necessary, pruning other varieties can help increase production. Here are some pruning tips:

● Remove early fruit to allow the plant to produce more vegetation (this will ultimately increase your yield). If more than 1 fruit develops at a node, thin to 1 fruit. The exception is the smaller pickling varieties, which can handle growing more than 1 fruit at the node.
● Trim the vine when it reaches the point where you want it to stop; this will allow the vine to branch at the nodes to produce lateral stems that will add to your cucumber harvest.
● You can also trim the tips of these laterals to keep the plant in a controlled area.
● Don’t go overboard with pruning or you’ll end up with a very dense plant canopy, which doesn’t allow sufficient light to reach the fruit.


When will those delicious cucumbers be ready for your salad bowl?
You can expect to harvest 50–70 days after germination.
Most varieties are mature at 8–12" long, but smaller cucumbers are edible. You can pick them at any size, as long as you don’t allow them get overripe. Overripe cucumbers appear smooth, bloated and yellow.)
Check your plants at least twice a week, and harvest frequently to allow for additional fruit to develop. Keep an eye on those plants! Cucumbers grow very quickly under the right conditions.
With proper care, you can expect to get 1–4 lb of cucumbers a week for roughly 8–10 weeks.

When to replace your plants

Excessive heat will stop the plant from producing fruit and turn the leaves brown. This is the sign that your cucumber vine should be removed from the Tower. You’ll also want to remove any plants from the Tower if they have excessive insect or disease problems as indicated in the Managing Pests section.