You received your new carnivorous plant in the mail and planted it (if shipped bare root). Now it’s time to sit back and enjoy, right? Not so fast. Over the next few days, your plant will go through an important adjustment period as it recovers from shipping and gets used to its new environment. During this adjustment or acclimation phase, there are several things you can do to help make the transition for your plant easier.
All of the plants that come from our nursery are used to humidity between 50-75%. However, your plant has spent several days in the mail sealed in damp wrapping which increases humidity to higher levels. If the humidity drops too quickly after arrival, the plant’s roots may not be able to replace water lost through the leaves fast enough and the plant may start to wilt, blacken, or shrink in size. This is known as transplant shock and it can be especially pronounced with bare rooted plants if not managed properly.
How do I control humidity levels?
1. To help your plant slowly adjust to lower humidity and give the roots time to reestablish, we recommend sealing the potted and watered plant in a large freezer bag. This will keep the humidity closer to the levels the plant experienced during shipping. Leave the pot in the sealed bag for 2-3 days. See note below about using this method for tropical and Mexican butterworts.
2. After 2-3 days, peal open a corner of the bag so the top is about 20% open (see image below). Cutting a corner of the bag off or poking holes in it works too. This will drop the humidity around the plant slightly but not enough that the roots will struggle to keep up with replacing lost water.
3. The following day, widen the opening in the bag by another 20%.
4. Continue increasing the size of the opening in the same manner each day until the bag is fully open. By this time, the plant should be acclimated to the humidity levels in your grow space. If you notice wilting during this process, it may be a sign you are dropping the humidity too fast. Give the plant a chance to re-hydrate and try opening the bag in smaller increments over a longer period of time.
A humidity dome with adjustable vents, an empty fish tank, or clear plastic container can also be used for acclimation instead of a freezer bag as long as the there is a way to control the size of openings. If you’d like to fine tune the humidity even further, you can invest in a small hygrometer like this one.
Note: When acclimating tropical and Mexican butterworts, we recommend starting with the bag half open at the beginning rather than fully closed. Butterworts don’t require as much humidity initially compared to other types of carnivorous plants. In fact, too much humidity could put them at unnecessary risk of crown rot.
What about airflow during the acclimation phase?
Good airflow is important to prevent mold growth and aid in photosynthesis. During acclimation though, too much airflow can make it hard to control humidity and the plant will dehydrate. Since the acclimation phase is temporary (a week and a half at most), less airflow at first is ok. More will be introduced naturally as you open the bag or container.
Tip: It’s best to start with new media when acclimating bare root plants, preferably a mix that contains well rinsed and/or sterilized ingredients like ours. Good airflow becomes much more important at the very beginning if you are reusing soil. Used soil has a much higher spore and bacteria count and can overwhelm a new plant more easily than using fresh soil.
Can I mist my plant to keep the humidity high?
For butterworts, sundews, and other dew-producing plants, we do not recommend misting. Misting can cause unnecessary stress by washing away the dew the plants work hard to produce. This means they will have to expend extra energy replacing it. For other types of carnivorous plants like Nepenthes and Heliamphora pitcher plants, misting can be beneficial. A humidifier or fog machine running on timed intervals works well, however sporadic or manual misting will only raise the humidity temporarily and it will be difficult to maintain consistent levels around the plant.
Proper temperatures are important as your plant recovers from shipping and adjusts to it’s new environment. For many carnivorous plants, keeping daytime temperature between 65 – 82°F during acclimation is ideal. While some prefer slightly higher or lower temperatures, going above 82°F during acclimation can cause unnecessary stress for most plants.
Acclimating plants to humidity levels using a plastic bag or dome can sometimes present a challenge with heat build up. The temperature in a sealed bag left in the sun, even indoors on a windowsill, can skyrocket to 100+ °F in no time due to the greenhouse effect. The hygrometer we mentioned earlier also doubles as a thermometer and can help monitor temperatures. Offsetting humidity and light acclimation (explained below) is a good way to help minimize heat build up as well.
Tip: Soil mass can have a significant affect on temperature (and moisture) stability and is worth considering when growing carnivorous plants, especially if they will be outdoors. Plant roots in a large pot of soil or planted directly in the ground will heat up and cool down slower than those in a small pot. Gradual temperature shifts will lead to happier plants.
At this time, we grow most of the plants in our nursery using either artificial light or filtered sunlight. This means they aren’t used to high levels of UV radiation from direct sun. If you plan to grow your plant outdoors, it will be important to adjust it slowly to this more intense form of light. Sometimes you can do this at the same time as humidity acclimation with extra care that the plant doesn’t overheat. For the safest route though, adjust the light levels after humidity acclimation to keep temperatures lower.