What is the Right LED Wattage for a 4×4 Grow Tent


A lot of our growers find that our 4×4 grow tent is a perfect size for their homes and their growth goals. But if you have just switched or are planning to move from a 4×2 or smaller size to a 4×4 tent, you probably are considering how to match the LED grow light wattage for a 4×4 grow tent.

In this post, we want to focus on LED grow lights. We should be aware that off-brand lamps can be dangerous and unreliable, and likely will not be a great long-term solution for your indoor growth.

Vivosun Grow Tent

Why should you choose LED grow lights?

Grow lights are a necessity for indoor growing, especially in a grow tent. When choosing a light, we want to simulate the perfect lighting conditions created by the Sun, since the spectrum produced by the Sun is exactly what plants use in their natural environments to photosynthesize. LED lights also use extremely low energy and generate very little heat. They can also provide a full spectrum of light that will take care of a plant through every stage of growth. Generally speaking, different colors on the light spectrum play different roles in plant growth.

Blue light promotes the growth of stems, branches, and leaves, while red light promotes the growth of buds and flowers. In addition, green and yellow light also play roles in helping plant growth, however, for most home growers, the focus is on blue and red. This is why when you search for LED grow lights online, the LEDs are shown as purple, a mixture of blue and red.

Tips for choosing an LED grow light for your 4×4 tent

How many watts per square foot for LED lights?

According to our current data, the average wattage required per square foot is 32 watts (although this also depends on the plant, so we are taking averages here), so a 4×4 tent theoretically requires 512 watts for complete coverage. This number can float between 500 watts and 600 watts. In actual use, many LED manufacturers will use more energy-saving bulbs, so the LED light watts in use are often lower than this range. It’s important to make sure you’re buying from a trusted manufacturer.

How mant watts for 4×4 grow tent?

To determine the appropriate wattage for a 4×4 grow tent, it’s important to consider the size of the growing area and the type of plants you plan to cultivate. Here are some general guidelines:

  1. Vegetative Stage: During the vegetative stage, when the plants are growing their stems and leaves, a wattage of around 200-400 watts is typically sufficient for a 4×4 grow tent.
  2. Flowering Stage: When the plants enter the flowering stage, they require more intense light. For a 4×4 grow tent, a wattage range of 600-1000 watts is recommended.

It’s important to note that these are approximate values, and the actual wattage requirement may vary depending on factors such as the efficiency of the grow lights, the desired light intensity, and the specific strain or species of plants you’re growing.

Generally, it’s advisable to start on the lower end of the wattage range and gradually increase the light intensity as needed, to avoid light stress or heat issues. Additionally, proper ventilation and temperature control are crucial for maintaining a healthy growing environment.

If you’re using LED grow lights, which are more energy-efficient, you may be able to achieve similar light output with lower wattage compared to traditional high-intensity discharge (HID) lights like metal halide (MH) or high-pressure sodium (HPS) bulbs.

What plants can you grow in a 4×4 tent?

A 4×4 grow tent provides a decent amount of space to cultivate a variety of plants, both for vegetative growth and flowering/fruiting. Here are some common plants that can be grown successfully in a 4×4 tent:

  1. Cannabis: This is one of the most popular plants grown in indoor tents. A 4×4 tent can accommodate 4-9 cannabis plants, depending on the strain and growing method (e.g., Sea of Green, Screen of Green, etc.).
  2. Tomatoes: With proper support and pruning, you can grow several tomato plants in a 4×4 tent and enjoy a continuous supply of fresh tomatoes.
  3. Peppers: Both hot peppers and bell peppers can thrive in a 4×4 tent, with room for multiple plants.
  4. Herbs: A variety of herbs, such as basil, cilantro, parsley, mint, and others, can be grown together in a 4×4 tent, providing a steady supply of fresh herbs for cooking.
  5. Leafy greens: Lettuces, spinach, kale, and other leafy greens can be grown in a 4×4 tent using hydroponic or soil-based methods.
  6. Strawberries: With the right setup, you can grow strawberry plants in a 4×4 tent and enjoy fresh berries.
  7. Microgreens: Microgreens, such as broccoli, radish, and sunflower sprouts, can be grown in high density in a 4×4 tent.
  8. Flowers: Various flowering plants, like marigolds, zinnias, and gerbera daisies, can be grown for ornamental purposes or as companion plants in a 4×4 tent.

The ideal plant growth spectrum

As we mentioned, different stages of plant growth require different colors of light. Excellent LED grow lights need to cover the whole cycle of plant growth and must provide the necessary light spectrum for those various stages of growth.

By combining different wavelengths, LED grow lights can provide either the full light spectrum or variations of the color spectrum so that you can emphasize certain wavelengths that match the specific period in the growing cycle. When you are looking for a new lamp, you’ll want to find a LED system that covers the entire light spectrum but if you prefer, one that also can be adjusted to specific growth periods.

Light intensity

Uniform Light Coverage

VIVOSUN VS4000 grows the light intensity

The way plants grow at various stages of growth is, on one hand, affected by the spectrum it receives, and on the other hand, by the intensity of the light, measured in Photosynthetic Active Radiation (PAR value, measured as PPFD).

For this section, we’ll mainly discuss how to think about finding the right intensity. Too high or too weak of light intensity can have a potentially damaging effect on your plant’s growth. Each plant requires a specific lumens coverage for a given area. Cannabis, for example, requires between 250-1200 PPFD which depend on the growing stages.

Wrap-up Right LED Wattage

Plants have a variety of lighting needs throughout their growth cycle, including both the color of the light and the intensity of light. When you are choosing a new fixture for your 4×4 grow tent, you’ll want to consider wattage, the type of plants you’re growing, and factors like the light spectrum, lumens, output, along with cost, electricity usage, and how much heat the lamp will produce. Take these ideas as a starting point rather than a comprehensive list, growing is as much reading as it is planting, but the results are worth it!

If you are looking for powerful coverage and a complete light spectrum, the VS4000 grow light is our go-to. Although it is only 400 watts, the lamp produces 2.9μmol/J, far exceeding the energy output of other grow lights on the market. The VS4000 also comes with a dimming knob that makes it adaptable to different growing periods by adjusting its output from 25% to 100%.

If you are just starting to set up your 4×4 space, you may also want to consider buying grow tent kit, which offers all of the necessary equipment to start growing, including a tent, a light, ventilation, and a number of handy accessories.

If you have any questions, please don’t hesitate to reach out to us!

And be sure to check out our other blog posts for useful tips on becoming a great grower!

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