By Maddy Hogan

We’ve harped on the importance of light and watering when it comes to indoor plants and now we are ready to close the loop by discussing all things indoor potting soil. Arguably one of the most important factors in an indoor plant's health, the soil is where plants obtain their nutrients, water, and support. Let’s dive into indoor plant soil, soil nutrients, and additives that will allow your indoor plants to thrive. 

Soil Nutrients

Just like humans need water and nutrients to survive, our indoor plants need nutrients to grow and remain healthy. Of all the nutrients required, the most important macronutrients are nitrogen (N), phosphorus (P), and potassium (K), which is often referenced as NPK percentages on soils or plant food nutrients. Nitrogen helps the plants produce chlorophyll that gives plants their green coloration and is essential for indoor plants to turn sunlight into energy via photosynthesis. Phosphorus assists in the development of a plants roots, flowers, and in some instances fruits, while potassium is required for overall plant health and the battling of disease and pests. While macronutrients are the most important, indoor plants also need secondary macronutrients and micronutrients to assist in important cell function, chlorophyll production during photosynthesis, and long-term disease resistance.

When choosing your indoor potting soil, it is important to take these macro and micronutrients into consideration. Indoor potting mixes, like those from The Good Dirt and Black Gold that we use at Riza, are typically a mix of peat moss, perlite, or vermiculite in addition to soil, bark, and any gritty rock-like texture. This blend of substances in indoor potting mixes supports a nutrient balance, while allowing indoor plants to retain water while also draining appropriately. 

Mushrooms & Fuzz

With nutrient-dense soil, especially during the shift from cool winter to warmer spring months, the appearance of mushrooms or fuzz may occur on your indoor potting soil. The conditions for mushrooms or fuzz to appear on your indoor potting soil usually means that your soil is too damp or soggy. The mushrooms and fuzz themselves are typically not harmful to your indoor houseplants, but indicate that a consistently soggy soil could be an issue. It is important to allow your plants to dry out for longer periods of time during cooler months and by limiting the prolonged moisture levels in the soil, you will limit the presence of mushrooms or fuzz growing in your indoor potted plants. 

Mushrooms are a representation of a fruiting body of fungi that lives in a nutrient-rich soil. These fungi feed on organic matter within the soil that is decaying, such as fallen leaves or roots. This increases in a moist environment or when your indoor potting soil retains moisture for longer periods of time, allowing the decay process to accelerate and mushrooms to appear. Fuzz in your indoor soil is a display that your soil contains beneficial fungi that help break down organic matter in the soil, providing a symbiotic relationship with the roots and overall health of your indoor plants. 

Soil Additives

In addition to choosing a nutrient-dense potting soil for your indoor plants, there are also several additive substances that we want to educate you about. These substances can be beneficial on a case by case basis and are dependent on other factors such as the type of plant, what zone you reside in, and what indoor lighting your plant will have in its space.

It is important to read soil nutrient and additive instructions carefully, or speak to a knowledgeable team member at the Riza store, because over-fertilization can occur which can damage the roots or leaves (and future leaves) of your plant as a result of nutrient burn. The same goes for general fertilization with watering, we recommend fertilizing your plants once per month during the active growing season of April - October. 

Riza has a Soil Bar in our Downtown Napa location at 1300 1st Street, Suite 355 in Napa, where we can re-pot all your indoor plants this spring and get them prepared for the active growing months this summer. All the additives and nutrients mentioned in this post can be found at our Soil Bar or in the fertilizers we carry. Give us a call or swing by in-person to chat about what your indoor plants need, we are happy to help you all have a thriving indoor plant scene!

By Maddy Hogan

Rare plants are often highly sought after because of their coloring and growth patterns, but it is important to point out that what truly makes these varieties rare is the scientific and genetic traits, slow growth and development, and care requirements. We will dive into a few of the most popular rare plants that Riza carries in our Rare Plant cabinet by our potting table in the rear of the store. If you visit us in person, we are always more than happy to unlock the cabinet and provide details about how to care for any of our rare species.

A common misconception is that rare plants need to be kept in a cabinet like they are in our shop, we just provide this environment to help the plants grow and achieve their full potential. Our rare plant cabinet is equipped with grow lights, a heating pad, a humidifier, several small fans, and a gauge to monitor the temperature and humidity levels within the cabinet. These conditions help create an ideal climate for rare plants to grow faster, but as previously mentioned they are not required to own a rare plant. We also keep our rare plants in the shop in the greenhouse cabinet because the back of our retail location does not have abundant natural light, so this assists in keeping the plants happy and healthy. So long as you are able to provide proper light conditions and watering in your home, these rare species will do just fine and bring you lots of joy.

A popular choice that is gaining popularity in the plant community is the Pink Princess Philodendron for obvious reasons, the stunning bright pink variegation that appears in its leaves. The Pink Princess Philodendron, like other philodendrons, is an easy to care for plant that survives in a wide variety of conditions. The Pink Princess Philodendron prefers bright indirect light, refer to our guide on light conditions here, and a soil that will retain some moisture but is also well draining. These plants prefer higher humidity to grow, which can be achieved via a humidifier, pebble tray with water, or regular misting. 

The Pink Princess Philodendron is a cultivar of the Philodendron erubescens plants, meaning that it has been cultivated and bred specifically for certain traits. This is what results in the pink variegation, a genetic mutation that affects the Pink Princess Philodendron’s chlorophyll productions, meaning less chlorophyll in the dark green leaves which produces the pink coloration in the leaves. This genetic mutation has been propagated and modified by plant breeders to produce the desirable Pink Princess Philodendron traits that are better suited for environmental conditions present in our homes so that these dream plants can survive more effectively. 

A second favorite, the Monstera Albo, is another stunner that is relatively easy to care for. This gorgeous plant completely lacks chlorophyll in portions of its giant leaves, due to a mutation in the chloroplasts in the plant’s cells and contains genes that regulate the production of anthocyanin pigments. This results in that highly coveted all white variegation in Monstera Albo leaves. Similar to the Monstera Deliciosa, the Monstera Albo is a natural climber and will be best supported by a moss pole or trellis, both of which we have available in our First Street Napa location, and prefers bright indirect light and moist soil. Similar to the Thai Constellation Monstera that is detailed in our newsletter this month, these plants are more sensitive to having their soil dry out completely and prefer a soil that holds moisture while still being well draining. 

Our third, and most vast group are rare anthuriums, which are highly sought after by plant collectors for their unique beauty, heart-shaped leaves, and challenging growth. Anthuriums have dark green and velvety leaves with defined silvery veins. As a diploid species, rare Anthuriums prefer bright indirect light and well-draining soil. They prefer to have the soil dry out completely in between sparing waterings when the top inch of the soil is dry to the touch. Fertilizing Anthuriums every two to three months during the growing season from April to October.

A commonality amongst all of these plants is that they are slow growers due to genetic mutations that plant breeders have focused on. These genetics are what make the plants rare and with stunning beauty, be it pink leaves, albo leaves that completely lack pigment, or the long elegant leaves of an anthurium with the silvery defined veins. A majority of rare plants prefer bright, indirect lighting conditions, well-draining soil that also retains moisture, and the willingness as a plant owner to provide the proper care and environment to ensure your rare plant doesn’t just survive, but thrives!

By Maddy Hogan

You know those tiny pesky insects that fly right into your face when you are near a screen that appear to become more common in the cooler winter months? Those small dark gnats are fungus gnats and they are often living and breeding in your indoor plants soil. In comparison to other indoor plant pests, fungus gnats are more annoying than physically damaging to your plants and are relatively easy to combat or eradicate. 

Fungus gnats get their name because they are feeding on the fungus in your indoor houseplants. Fungus in the soil is very common, especially when using a nutrient dense soil that provides many benefits to your plants. Adult fungus gnats lay their eggs in the top inch of damp soil when the larva matures. If you find a few pesky black adult fungus gnats swarming, check any houseplants with damp soil or excess moisture for a larva, silvery crawlers in your soil. Again, even the larva will not be harmful to your houseplants, however your adult fungus gnat population will quickly increase. 

There are lots of solutions to prevent and combat fungus gnats that are safe for your houseplants. When you notice adult fungus gnats, it is important to identify which houseplant has the larva. Winter months are more common because it takes plant soil longer to dry out completely, leading to growth of fungus. If repotting your plant is not an immediate option, it is best to let the soil of your plant dry out completely. Once the plant soil is dry, sprinkle mosquito bits on top of the soil layer and water over them to activate. The mosquito bits will kill the fungus gnat larvae and continue to do so with each watering. We sell mosquito bits online and in our retail shop and when you purchase our repotting service, we include mosquito bits in the soil to help with the prevention of fungus gnats. Another prevention method is to put potting sand on top of your soil as adult fungus gnats cannot penetrate potting sand to lay their eggs.

In order to catch the adult fungus gnats, there are a handful of options depending on the severity of your infestation. Sticky traps are highly effective and are easily stuck into the soil to immediately begin catching the adults. Again, depending on the severity of your infestation, you will want to change out the sticky traps every few days or weekly to make sure you continue to catch the adult fungus gnats. A second option is to put out a small dish or bowl with a dish soap and water mixture to trap any flying gnats and refresh weekly. Finally, and the option we have many of at the Riza shop because fungus gnats are common and a large part of plant parenthood, are the Katchy Indoor Insect Traps. These are quiet fans that suck the fungus gnats out of the air and draw them towards an internal sticky trap, instead of staking them visibly in your plants soil.

By Maddy Hogan

Lighting is one of the key components to keep your plants thriving indoors. We often tell our customers at Riza that there is a ‘plant for everyone’ and that also applies to lighting, there is a plant for every light condition in your home. Whether you have a bright room with large south-facing windows or a more dimly lit area with a north-east facing orientation with space available further away from the window, there is a plant for you.

The brightest light will be in southern and western facing windows. Western facing windows will receive the most light in the afternoon, whereas eastern facing will have bright morning light. Northern facing windows get the least amount of direct sunlight shining through them, but there are plenty of plant options that will suit your conditions whatever they may be. In addition to directional facing of your windows, sunlight strength is also varying based on distance from the window. The brightest and most effective light will be right next to or in front of the window, where the further away from the window in any direction, including to the side of the window, will reduce the effectiveness and sunlight strength which can impact the health of your plants. 

We have created the infographic below to assist in visualizing the information mentioned above.

Here are some plant recommendations based on the 4 zones defined in the infographic above:

Zone 1:

• Bird of Paradise
• Fiddle Leaf Fig
• Ficus Audrey
• Rubber Trees
• Sago Palm
• String of Hearts
• String of Pearls
• Succulents & Cacti
• Yucca

• Airplants
• Aglaonemas
• Alocasia
• Anthurium
• Arrowhead
• Begonia
• Calatheas
• Croton
• Dieffenbachia
• Dracaena
• Ferns
• Fittonia
• Hoyas
• Marantas
• Monstera
• Orchids
• Peace Lily
• Peperomia
• Philodendron
• Pilea
• Polka Dot Plant
• Pony Tail Palm
• Pothos
• Rhaphidophora Tetrasperma
• Schefflera
• Snake Plant
• Spider Plant
• Staghorn Fern
• ZZ

• Aglaonemas
• Arrowhead
• Dieffenbachia
• Dracaena
• Fittonia
• Monstera
• Neanthe Bella Palm
• Philodendron
• Pony Tail Palm
• Pothos
• Snake Plant
• Spider Plant
• Tradescantia
• ZZ

Zone 4:

• Dracaena
• Fittonia
• Jade Pothos
• Neanthe Bella Palm
• Snake Plants
• ZZ

By Maddy Hogan

The woman behind the store Riza Plants is Napa-native, Alyssa Piombo. Piombo grew up admiring plants from a young age, initially inspired by the garden at her grandparents home, and continuing into her college education years in Hawaii. After completing her business degree, Piombo returned home to Napa and worked at a local nursery prior to taking the plunge and starting her own venture, Riza Plants. 

Sticking to her proud Grecian heritage, Piombo named the store Riza, Greek for ‘roots’. It is in this plant store that she has created the foundation for plant enthusiasts to not only enjoy, but be educated about plants as well. Her inspiration for Riza was to meet a demand in her hometown and pair that with her passion for plants. Since her opening in October of 2020, Piombo has been impressed and comforted by the huge sense of community she has experienced being a small business owner in Napa. It has brought her closer to her hometown and allowed her to not only learn from others, but also be positively influenced by them as well. 

Plant mom/business owner is only one of Piombo’s titles, she is also a human mom and most recently, a dog mom. When asked about what motivates her most as a mom, Piombo stated ‘I want to be a role model for my child to choose a career that is out of the norm.’  Her hard work and dedication is exemplified in all that she does, be it at home with her family, or running around her retail plant store, there is no denying that Piombo is passionate about life. 

She is extremely patient and encouraging of new plant parents that are weary of bringing home new greenery. When asked what her best advice is for those hesitant about owning plants, she told us ‘there is a plant for everyone. If you travel a lot and need a plant that will thrive on neglect, then a snake plant or ZZ are the choice for you. If you work from home and have the time to attend to a needier plant, there are lots of options from calatheas to more rare species. There is even something to offer those with pets that need a non-toxic option just in case your furry friends decide to have a little snack.’

To know Piombo’s passion for plants is to walk into Riza and experience the atmosphere yourself. Located at Napa’s First Street in downtown at Suite 355, between Eiko’s and Copperfield’s, you are sure to find Piombo full of life and fresh detoxified air in her stunning retail shop. Stop by and check out her latest offerings, pick up an educational plant book, or get your current plant babies repotted and ready for the growing season!

By Maddy Hogan

Frost advisories typically occur in the late fall and early spring as the seasons are shifting in and out of winter. Temperatures can be anywhere from 32 degrees to 36 degrees Fahrenheit for frost to occur, it doesn’t necessarily need to drop below freezing temperatures. When the temperatures drop below 32, that can cause a freeze which can cause more devastating damage than a frost. 

Tropical and subtropical plants that have spent warmer months outdoors can be impacted during frosts, but there are several ways to combat potential damage.  

1. Water plants thoroughly. Wet soil is capable of holding significantly more heat than dry soil. This heat will rise to the top soil layer, approximately 2-3 inches deep, and warm the layer exposed to the frost. Watering in combination with a blanket or sheet covering will help create a warmer and more humid environment to prevent frost damage.
   
   
2. Cover plants with a blanket or sheet. Loosely cover plants with old blankets, sheets, or towels and ensure that the covering reaches the ground on all sides of the plant. This creates an insulation barrier around the plant, and when paired with thorough watering, will allow the plant to retain heat and humidity to ward off frost. During an extended cold front, it is important to remove any plant coverings during the day as the insulation effect can create too warm of an environment and cause plants to overheat.
   
   
3. Move plants indoors or under covered areas. For easy to move plants, bring the pots into your home, greenhouse or garden shed, or garage. Any form of insulation will prevent frost from impacting your tropical and subtropical plants, so even moving plants from full exposure to under an awning or overhang can reduce the negative impact of frost.

These quick tips can help you prepare and prevent damage to your tropical and subtropical outdoor plants. A combination of these will reduce chances of frost damage to plants and overall impact to your plants growth. Stay up to date on weather alerts for your local zones to make sure you are covering your plants when the temperature drops!

By Maddy Hogan

Prayer plant is the common name for plants that belong to the genus Maranta and Calathea which have ornately decorated leaves that appear hand painted. These beautiful leaves rise and fall in accordance with a circadian rhythm that mimics the daylight hours and makes them appear to be ‘praying’. The process of the praying leaves is called nyctinasty and is believed to be an adaptation that allows for maximum light absorption by changing the pressure of the water in the leaves of the plant.

Native to tropical and humid climates, these plants provide more than just a scenic sprucing to a home, they serve functions. In Brazil, it is very common to see the wider and broad leafed calatheas used for wrapping food, while the more long and narrow leaves are used for basket weaving. Some of the species have edible nodes on the root systems as well, but for the purposes of your houseplants, we do not recommend taste testing them even though they are considered non-toxic and pet safe! 

Because these species originate in tropical regions and are below the canopy dweller, they can be particular when it comes to their light and watering requirements. Calatheas and Marantas have beautiful but sensitive leaves that can burn in direct or intense sunlight. A sign of burnt leaves is a yellow tint with the ornate patterns fading away. The great thing about calatheas and marantas is that while their leaves are sensitive to light exposure, they are resilient to trimming with snips. If you find your plant with brown or crispy edges, feel free to clean up the edges with your snips, the leaves will survive just fine.

They prefer a bright indirect to moderate light and a consistently moist, but never soggy, soil. The soil moisture levels can be what calathea and maranta owners find the most frustrating when starting out with these plants. If the plant is overwatered, resulting in a soggy dark soil, the leaves will begin to yellow and have the beautiful ornate patterns fade from them. If the plant is under watered, allowing the soil to dry out too much, the leaves will typically curl and become brown and crispy around the edges. Moisture meters can be a huge asset to those that are learning about what moisture level their plants need and we carry the Classy Casita ones in our downtown Napa location.

Another element that can assist with the retention of moisture in the soil is creating a humid environment for these species. Humidity can be achieved in a variety of ways, whether it is regular misting on the leaves and topsoil, putting multiple plants together in one area to increase water vapor expulsion, adding a humidifier to the room, or a pebble tray with water underneath the potted plant. While calatheas and marantas do love humidity, do not let this be a deterrent because it is not mandatory to create additional humidity. Our indoor environments naturally have sufficient humidity for these plants to live a happy and healthy life.

By Maddy Hogan

As the seasons change, your plant care will need to be adapted to take into consideration both dormancy in house plants and environmental changes.

Most indoor plants are native to tropical regions that enter dormancy during environmental changes, such as decreased rainfall or increased temperatures. Dormancy is a period of time when a plant’s growth cycle slows, or completely stops, to accommodate for these environmental changes. The tropical house plants we have indoors will enter a period of dormancy during the winter months as the temperatures cool and become inconsistent, there are fewer hours of daylight meaning there is less photosynthesizing going on, and the humidity in the air is lower, all requiring less water and no fertilization for your plants. 

Below we dive into the details that will help your plants thrive throughout their dormant period, even though their growth will be slowing down.  

Seasonal Environment Changes & Impact

Lighting - sunlight during winter months is less intense, lower in the sky, and daylight hours are decreased. This will mean that plants need to be moved closer to a window to gain similar sun exposure that they did during the summer months. With fewer hours of sunlight that is less intense, plants will also take longer to dry out between waterings.  

Watering - recommended watering for most tropical houseplants is when the top 1-3” of soil is dry to the touch or every 7-10 days. During the winter months when plant growth slows, the water requirements decrease to when the soil is nearly completely dry to the touch or every 21-30 days. While it is important to allow plants to dry out more during the winter months, it is important to keep an eye on furnace or fireplace use as this can pull moisture out of the soil faster, which will further stress a dormant tropical plant.

Boosting the humidity in your home can also benefit your tropical house plants during winter months. Humidity can be achieved in a number of ways. You can group multiple plants together or in a specific area of your home to increase water vapor exhalation, thus creating an overall more humid environment for your plants. You can place pebble trays with water underneath your potted plants, just ensure that the pot is not actively soaking in the water as this will lead to the root system absorbing too much water. Lastly, you can mist your plants with a spray bottle or use a humidifier. 

Drafts & Fluctuating Temperatures - the winter months can bring cool drafts near windows and doors, as well as the extended use of furnaces or fireplaces. Indoor plants are sensitive to drafts on either extreme and it is important to ensure that cold or hot drafts are not impacting them. If you live in climates where there can be severe cold weather, it is important to make sure that the environment for the indoor plants does not drop below 50 degrees Fahrenheit for extended periods of time.

Maintenance - similar to watering reduction, indoor tropical plants do not need fertilizer during the winter months. Because the plants have entered dormancy and are not actively growing, you can hold off on fertilizing or any soil boosting nutrients until the spring. We recommend fertilizing once a month from April - October. 

Pests tend to subside during the cooler months, however plant owners should never completely let their guard down when it comes to these pesky critters. Pests are completely natural and part of the plant owning process, similar to how fleas are part of the pet owning process. Preventative measures are the strongest measures, so make sure to continue to wipe your plants leaves clean to ensure they can absorb all the light they can and to remove any open invitations for pests to move in. 

If  you are moving your plants from outdoors to indoors for the winter months, we recommend thoroughly inspecting your plants, particularly focusing on the underside of leaves, at the base of the plant near the soil, and inspecting the soil for any larvae or adult pests. A solid spray down with a hose will ensure that any stragglers are taken care of and we suggest a preventative spritz with an all year round solution. We recommend the Espoma Insect Control Spray that we carry in our downtown Napa location. 

Mosquito bits are also useful during the winter months when plant owners tend to overwater as they try to gauge how much longer their plants take to dry out. With consistently moist soil comes fungus gnats, which can be combated with a small sprinkle of mosquito bits that are activated when you water over them, killing the mature fungus gnats and their larvae. 

We hope these tips serve you well during the dormant months ahead. If you have any questions you can always reach on social media, email, or in-person at the shop!