The Almond Agaricus mushroom is a summer producer that can grow in a wide variety of composts. It thrives in warm environments, nicely adapting to porch and window box plantings and protected culture in the greenhouse, but like every other mushroom, it requires moisture to grow which often means occasional watering to keep the seeding zone moist. Its warmth loving nature means it is cold sensitive and will only produce as long as temperatures stay above 40°F. Fruiting success is directly correlated to maintaining the moisture content of the substrate (your mix or compost, soil, and spawn), so be sure to start with a properly hydrated mix prior to inoculation and planting. Follow the steps below for planting your Almond pots or beds.
Note: Bottle spawn is similar to bag spawn biologically but bag spawn is often used for larger scale plantings. If you wish, you may use the bottle spawn inoculation method (Step 3) with bagged spawn (simply placing the spawn in a narrower band of compost) but if you wish to get faster fruiting and higher yields add more spawn, up to a 40:40:20 mix of potting soil:compost:spawn ratio.) For maximum yields, use 5 lbs of spawn to a 45-55 liter pot filled with approximately 50:50 potting soil to compost, which will get you close to the 40:40:20 ratio.
Preparing your Mushroom Bed Material
Step 1. Prepare the Compost
Compost should be fully finished (so you can't tell what the starting material was). A variety of plant-based composts work great, even store purchased varieties. Compost should be maintained between 60-70% moisture content. Grab a handful of compost and squeeze it. When you open your hand, it should stick together in a clump and you should see water on your hand.
Step 2. Prepare the Potting soil
Prepare your potting or loamy garden soil mix: If you are using potting soil it usually needs to be hydrated. An effective way to keep your entire mix hydrated properly for a great moisture content at inoculation, hydrate your potting soil so it is a little wetter than your compost. Grab a handful and squeeze: a few drops of water should squeeze out.
Planting Almond Agaricus
Method 1: Inoculating in a pot or planter with Bottle Spawn (proceed to Method 3 if planting in garden or raised bed)
The Almond spawn is planted near the compost and soil interface where it will grow and thrive if it is provided with a 4 inch layer of compost at the top of the soil. Small plantings benefit from this concentrated inoculation zone. You can grow the Almond as a crop all by itself in pots but it is easiest to plant leafy flower or vegetables as transplants or seeds along with the Almond. The plants will provide important shade and gas exchange to help nurture the mushrooms as they grow, and vice versa. Here's how to do it:
• Fill your planter 1/2 to 2/3 full with moistened potting soil.
• Scoop the spawn out of the bottle. Place chunks of spawn (small egg size) in a 6-inch grid pattern across the exposed pot surface and press firmly into place. (If the spawn is in crumbles after removing it from the bottle, form an egg shape and press together with your hand).
• Place a 4 inch layer of compost on top of the spawn and potting soil and smooth it level. It's best to start with a moist compost and water minimally during the 2-3 establishment period.
Now you can plant your seeds or transplants. You may wish to mulch the pot surface to keep the compost moist and avoid over-watering.
Next, watch for mushrooms! In 4-6 weeks from inoculation (depending on weather conditions), your pot may start to fruit.
Method 2: Larger planting: Using a bag of sawdust spawn for larger pots.
Prepare a 50:50 compost:potting soil mix
And blend together as in step 1. Add ½ -full bag of sawdust spawn; use the larger amount for faster fruiting but the smaller amount can be effective with a longer spawn run time. Break the spawn into egg sized pieces and gently blend into the soil mix. Pour it into the pot and make sure all the pieces of spawn are buried. Plant your favorite container plants. Maintain original moisture content with light watering during establishment, then water only as plant needs dictate.
Method 3: Planting in the garden with Bottle or Bag spawn
Time to plant:
Spring to early summer, after danger of last frost during warm weather conditions.
Time to fruiting:
As soon as 4 weeks after planting.
When they fruit:
Summer until cool down in the fall, single season.
Large white button mushroom that matures into classic Portobello shape. Almond Agaricus has a central white stem, a white-tan colored cap, and a veil during its immature stage that breaks away to reveal pale pink gills (gills darken to deep brown as the spores mature). Generally as large as classic button and baby bella mushrooms.
Flavor and texture:
Mild and tender, often with a hint of almond aroma and flavor. Flavor intensifies with dehydration.
Almond is best planted in compost that is layered under a plant or plants that will provide ample, leafy shade during the growing season. Tomatoes, eggplant, peppers and summer squash are good choices.
Follow the same steps as for planting in pots or planters (Step 1) laying a 4-inch deep swath of compost in a chosen location in the garden and press the spawn into the compost so it rests near the soil surface. Mulch over the compost to help keep the compost moist. *Note: Skip adding potting soil as it is only important for growing successfully in pots.
Method 4: Planting in raised beds
If you use drip irrigation in a raised bed, you can successfully raise Almond Agaricus. Hoe a 4-inch deep, 4 inches wide trench down the drip layer of the bed. Fill the trench with compost and inoculate an egg-sized piece every 6 inches. Mulch over the trench and lay the drip hose over the trench and water as necessary for the plants.
Maintaining and monitoring the bed during colonization
Maintaining moisture is the most critical factor for success. Outdoor beds may receive enough rainfall, but beds planted in protective structures (ex. cold frame) may need to be watered as frequently as several times a week. A top layer of mulch can really reduce the need to water. The top layer of compost may appear dry, pull away the mulch from the top of the bed. You should be able to see white mycelium cover patches of the surface of the compost after a few weeks. CAUTION: Beware of keeping the compost layer constantly wet, as this may drown the mycelium.
Watch for pinning mushrooms
Baby mushrooms will appear as solid white bubbles, usually at the base of plants, and will quickly enlarge. Within a week, mushrooms will be full size when the cap expands and drops its skirt. Gently pull the mushroom at its base and trim the roots off to keep the mushroom clean. You can eat the both the cap and stem.
Mushrooms will develop intermittently throughout the growing season and sometimes even in to late fall. You can bring the pots indoors and with occasional watering you can sometimes collect a few more mushrooms if the pots don't freeze.