 Bee populations around the world are declining. Human activity is part of the reason. Ongoing changes to the landscapes where bees normally thrive could be reducing their once bountiful array of nutritional food options. To learn how nutrients from plants shape bee performance, scientists experimented with the diet of red mason bee larvae. Their experiments were based on the concepts of ecological stoichiometry. This method of chemical accounting views organisms as the product of the available nutrients in their environment. Environments poor in essential minerals prevent the construction of organic molecules necessary for healthy growth. This approach makes it possible to link nutrient availability to nutritional balance in wild bees under fully controlled settings, something that's impossible to do in a field study. Bee larvae were fed one of several pollen mixtures differing in species composition and floral diversity. Specific species of pollen were related to specific proportions of five vital body building nutrients, sodium, potassium, copper, zinc, and phosphorus. The overall proportions of these minerals were used as a proxy for nutritional quality. Some mixtures contained the nutrients in the balanced proportions required for the healthy growth of red mason bees. Others were nutritionally imbalanced with reduced concentrations of some nutrients. A third group consisted of the same nutritionally imbalanced pollen mixtures but nutritionally supplemented to make up for this imbalance. Bee larvae fed imbalanced pollen mixtures experienced high mortality or under development. However, the addition of scarce nutrients to pollen diets led to the partial mitigation of this negative effect or reversed it completely. These findings offer two important takeaways. For one, the occurrence of certain plant species may be important for wild bees, as these plants may provide vital nutrients in favorable proportions. Second, the definition of what's healthy or balanced when it comes to nutrition is up to the bees themselves. It's not enough to provide abundant food sources for bees. Different bees require different amounts of essential nutrients. That could account for why commercially available pollen mixtures aren't always effective for bee conservation. There's a mismatch between the proportions of nutrients they provide and the proportion of nutrients bees need. Unfortunately, there is no single ideal mix of bee-friendly plants that can be used everywhere. Finding ways to make landscapes altered by human activity nutritionally balanced for wild bees could go a long way in conserving bee populations.