Light is one of the most critical and sensitive factors when caring for medicine, especially seedlings. In the first year of growth, seedlings can easily die off if exposed to too much light. Older plants can also be damaged by excessive exposure to light, both in terms of light intensity and length of exposure. Even an old hand at cultivation like myself can be challenged in maintaining the right amount of light exposure and duration in my sacramental gardens. There is a need for continual observation of the plants as the seasons change. What might be the perfect amount of sunlight in the springtime can quickly become damaging to plants as the summer progresses. Ignoring or miscalculating this optimum window of light exposure is likely the most frequent cause of challenges to the home gardener, especially with delicate seedlings. In today’s post, I will visually illustrate and discuss the consequences of too much or too little light on the medicine’s health.

Bless us with your light Creator so that through us, your medicine may reflect itself into our world in a good way.

The most common mistakes made in small home peyote gardens are by far, less than appropriate soil and/or light. Often people who plant medicine that is already of some size will use a standard commercial potting mix, or whatever natural soil is available to them. Less than optimum soil does not always result in plant mortality, but it can definitely limit the amount of thriving they will exhibit. The same way with light. Either less or more than optimum light might not permanently harm plants, but it should be corrected for them to thrive in the long term. There’s lots I could say about this but I’m lazy and will try to say it mostly with pictures.

Let There Be Enough Light

First, we need to discuss a particular word: Etiolation, the process of plants stretching to reach more light. Peyote reacts this way when it needs more light to grow properly.

Peyote plants that stretch this way usually exhibit a darker green color to their skin before, and as they begin to grow taller. At the beginning of this process the center parts in the seams have a lighter color as they rapidly produce new cells to stretch upward in an attempt to catch more light. Well lit peyotes tend toward more of a grey/green color and stay close the the ground, always wider than they are tall.

The reason you don’t see this dark green tall growth in nature is that only peyote seedlings that germinate in spots where there is neither too little or too much light survive. This is part of the reason for increasing the capability of cultivated seedling transplanting into the wild. Rather than one in a thousand seeds surviving to maturity, seedling transplants can reverse that failure/success ratio.

Plants that have grown tall from etiolation can be cut near the base and new “normal” tops will grow if exposed to more appropriate light intensity or durations. Any sudden increase of light intensity or duration in plants which are not cut first can severely damage them. It is important to make increases in light slowly so as not to burn the unaccustomed plant. Decreases in light intensity to stop burning can and should be done right away, with no transition time needed.

Not getting enough light is not good for the plant overall. One thing I’ve noticed is that less than optimum lighting will also reduce flowering frequency, and therefore, seed production. Another situation that arises from low light conditions is mite infestation. Growers commonly see this happen when light levels are just under optimum, but not so dim that it causes stretching. Mites thrive on a plant which is just healthy enough to produce enough nutrients for them to steal, but not so healthy they have immunity, and not so weak that they stretch.

Mites can be eliminated by using insecticidal soaps, oils, or pyrethrums. Gradually increasing light exposure to infected plants is a good way to avoid re-infestation. Plants will recover their normal skin tone after a few months of mite-free growth in proper light.

Don’t Let There Be Too Much Light

I recently visited a friend who was sad to have had a fairly large peyote plant burned on one half by the sun. This is a common mistake home gardeners can make who are hoping to help the plant by giving it more light, albeit too quickly. All these increased light moves need to be done gradually. Even watering a potted plant then replacing the pot pointing in a different direction can quickly burn the side accustomed to being pointed the other way. Plants which have been significantly burned can often recover with time. Sometimes the most efficient way to help them is to cut the damaged top, encouraging new ones to replace it.

Pro cacti growers often mark the sunny side of the pot with a spot of nail polish so that when moving plants they are oriented with the same sunny side as before. I run into this situation from spring to summer, if the plants changed direction in the previous winter. The lengthening days of late spring can start to burn the new sunny side of the plants. When this is an issue, I give extra shade to the plants until the next spring, by which time they will likely be adapted to the particular intensity and angle of the sun’s seasonal changes.

It is not uncommon when growing seedlings under natural light, for them to get overexposed to sunlight. I recently ran into this on seedlings germinated in summer. As fall approaches, the sun is lowering on the horizon and therefore more direct sunlight is hitting the windowsill than it was earlier in the year when its angle cast mostly diffuse light.

Overexposed seedling trays can be covered with a layer of cheesecloth to adjust light exposure until light intensity is lowered, either seasonally, or by relocation. Slightly browned seedlings tend to recover rapidly once light intensity is adjusted.

So I guess light and growing medicine is a bit like raising kids. For their own good you don’t want them being too intense or bright, but you don’t want them dim or shady either. I’ll have to think about that for a while. I wish you all a perfectly lit day.

Click below for next post

Lorax Dreams, Conservation Proposal