Gardeners growing under lights are starting to understand how important DLI is to their growing environment. References to K levels and distance from bulbs are long gone. These values are obsolete, especially when using LED lights to grow plants.

Now it is all about DLI, the Daily Light Integral. Get that right, and you can grow some great plants.

The problem is that DLI requires you to do some calculations, which nobody wants to do. That is why I developed a FREE DLI Calculator.

Key Takeaways

• Gardeners need to start using DLI to describe their lights.
• It is easy with the DLI Calculator

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What is the correct pot size for African violets?

The 2019 May- June issue of the African Violet Magazine clarified this by stating, “pot size should be 1/3 the diameter of the plant”. This is repeated on numerous sites providing growing information, including the African Violet Society of America, and it is stated almost daily in African violet Facebook Groups.

If a plant shows any signs of decline or problems and is in a pot larger than 1/3 the diameter, owners are immediately told to repot it into a smaller pot.

That advice and the 1/3 rule are incorrect.

Watch the video version of this blog post: https://youtu.be/03mihVFxkKA

Key Takeaways

• The 1/3 pot size recommendation for African violets is wrong.
• Taller pots are drier than shorter pots.

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Wick watering is a fairly popular way to water houseplants. The initial setup is more complicated, but once a pot is set up for wicking, you spend less time watering your plants.

This post looks at the underlying science and uses that information to debunk some common myths about wick watering.

Watch the video version of this blog post: https://youtu.be/D7WEMqPPAYw

Key Takeaways

• The size of the wick does not affect the moisture level in a pot.
• The wick can’t make the potting media too wet, but the technique can produce pots that are too wet for plants.

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There are four basic ways to water a houseplant: from the top, from the bottom, with a wick system, or with self-watering pots. Which is best? What are the pros and cons of each method?

Let’s look at the science behind each method to see whether they work and which plants actually prefer each one.

Watch the video version of this post: https://youtu.be/E8m2Aoh5ClQ

Key Takeaways

• All 4 methods work if used correctly
• Match the method to your environment and habits.

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If you scroll through online health forums, social media, or sensationalized health blogs, you have likely seen alarmist headlines claiming that a humble bowl of rice is poisoning you with toxic heavy metals. Some claim you should cut rice out of your diet entirely, while others insist that organic rice is somehow immune to soil contaminants.

Internet health claims are often rooted in a kernel of truth that gets blown entirely out of proportion. Let’s skip the fear-mongering and look at what actual scientific research tells us about arsenic levels in rice.

To watch the video version of this post, watch: https://youtu.be/oZOSkMTUCN4

Most fertilizer sold to gardeners uses urea as the nitrogen source, but most commercial greenhouses use nitrate as their main nitrogen source. Why?

I have been spending time in the African violet (AV) community, and most growers, including the African Violet Society of America (AVSA), recommend using nitrate rather than urea. But Schultz African violet fertilizer is very popular in this group, and it is mostly urea. In a test reported on by AVSA of the top AV fertilizers, one used only urea, and the other used no urea. A prominent breeder stated: “I’ve used fertilizer containing urea for nearly 30 years“.

I have used urea-based fertilizer for 50 years on all kinds of houseplants, and it seems to work, though recently some of my streptocarpus seedlings may be showing yellow leaves. It is time to understand the urea vs nitrate controversy in more detail.

Watch the video version of this blog: https://youtu.be/YdY5S7RUKMo