Using my quantum flux meter, I can measure PPF and PPFD output from my fluorescent grow lamps. Not enough light for the full-sun strawberry plant on the shelf, but just enough for small light-sensitive African violet plantlets I propagated.

To determine your average PPFD for a given lamp and space, take several measurements around the actual plant canopy (only the area where plants will be growing) from a specific distance from the light fixture. Average these numbers to get a meaningful PPFD value.

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When choosing a container for starting your seeds, look for one that is only 2 to 3 inches deep and has drainage holes. Reusing plastic pots from your last garden center purchase is always a great idea. Larger containers that hold more soil may cause problems for tiny seedlings, as they can hold too much moisture or wick moisture away from the small root system.

Before you reuse plastic pots, make sure to disinfect them to prevent the spread of disease.

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Switching between color spectrums and types of lamps can help you influence plant-growth habit and trigger different stages of development. You can also mix and match different spectrums of light.

Fluorescent grow lamps are available in varying spectrums that you can switch out in your fluorescent fixture. You can mix fluorescent tubes of different spectrums in the same fixture to create your own light recipe.

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Some seeds do not have a hard seed coat, but rather go into a dormancy period that can make germination a long affair. You will have to wake these seeds from their slumber using a process called stratification.

Stratification involves creating favorable environmental conditions in which the seeds would germinate in nature. Seeds and plants that go into dormancy typically come to life after the return of spring temperatures and rainfall. You must mimic the cycle of dormant winter season followed by natural germination season. Stratification involves exposing seeds to cold temperatures - typically in your refrigerator - for a period of time before attempting to germinate them. Check your seed packet for specific stratification recommendations.

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Citrus trees are heavy nitrogen feeders. Choose a fertilizer with a 2:1:1 or 3:1:1 ratio. There are special fertilizer blends labeled for citrus plants.

Apply a fertilizer to the soil at planting time, then fertilize monthly during the active growing season (late winter through summer) and once every two months during fall and early winter.

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We all kill plants, even us professionals. If you're wondering why your plant died on you, there are a few important things to remember about how plants live and grow. Plants need enough light, water, and carbon dioxide to drive photosynthesis. If they don't get enough of each or all, they'll be in trouble.

Respiration is how plants burn calories, and respiration doesn't stop just because the lights are out or you forgot to water. Your plants will burn energy even if there is not enough light, water, or carbon dioxide available. If those inputs remain limited or cease, eventually your plant will burn more energy than it can generate. Like this plant, which is now TOAST. Because I forgot to water it.

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Have you struggled to grow cucumbers, either in your indoor garden our outdoors? Often a lack of water is keeping your plants from producing as well as they could. Cucumbers produce fruit that contain a lot of water, so they must stay consistently moist for fruit to develop properly.

If you let your cucumbers go dry, you may see flower drop or your fruit might have a tough texture. Inconsistent watering can lead to blossom end rot, a deformity caused by a disruption in calcium uptake. To put an end to blossom end rot, keep soil or growing media evenly moist all the time.

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Many small two-band LED lamps can be used in standard home light fixtures, floor lamps, or spotlights. These small lamps typically fall in the 3- to 13-watt range and will be labeled as E6 or E27 base.

These individual low-wattage LEDs are useful for only individual houseplants like potted foliage plants or orchids. Do not expect them to light up a large area or to be suitable for multiple plants.

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