Starting Seeds Mash-Up: Spring 2014 Master Gardener Newsletter

By Wendy Hanson Mazet and JoAnne Skelly

Wendy: Starting Vegetable Seeds Indoors

Picture4The common vegetable crops that are good to start indoors include cucumbers, squash, pumpkins, watermelons, eggplant, tomatoes, okra and peppers. Starting your vegetable garden from seed is not only a rewarding experience, but fun for most avid vegetable gardeners. Many people start their entire vegetable garden from seed. This is a great idea when you want specific or hard-to-find varieties, or organically grown plants. It can also be very affordable.

Growing plants from the ground up is fairly easy with the correct tools and growing environment. All that is needed is a good soilless potting mix, quality seed, sterile containers and a bright, warm location. Then, with a little research, time, water and some tender loving care, you will have an abundance of beautiful seedlings.

First, choose good quality seed. If purchasing online or at a nursery make sure seed was packaged for sale this year. Older seeds will have lower germination rates, especially if not properly stored.

Second, choose a good quality soilless mix for starting the seeds. Never use your garden soil for starting seeds indoors. Garden soil can harbor microbes that cause diseases such as damping-off which will kill your young seedlings. Many gardeners have learned to make their own mix from recipes found online or in garden books. For very small seeds it is best to start them in a fine mix of perlite and vermiculite, or a peat moss based seed starting blend. These blends allow for excellent aeration, which is necessary for seed germination. If you choose a perlite/vermiculite mix, be sure to transplant your seeds once the second set of true leaves appear. These seedlings can then be transplanted into larger containers filled with an indoor seedling mix or potting blend.

Many seed packets hold a wealth of information including when to start the seeds indoors, how to transplant and care for the plants and harvesting information. In some cases, seed companies will put detailed information inside the packet, so open seed packets carefully; there may be historical information and recipes inside. Be sure to read the seed packets for proper planting directions. Not all companies provide an abundance of information on the seed packet; if this is the case you can do a little research for more details, or call your local University of Nevada Cooperative Extension office.

Here are some basic requirements for successful seed starting:

  • Light– Light is one of the most important elements when starting seeds indoors. Plants prefer a window with bright southern exposure. If you do not have a south-facing window, choose a bright area and add grow-lights, or cool-white or daylight fluorescent bulbs.
  • Soil– Monitor the planting mix to make sure it stays moist but not wet. Seedlings can suffer from rot easily when over-watered.
  • Temperature– Soil temperature plays a big part in indoor seeding success. For instance pepper and tomato seeds prefer to germinate in soil temperatures above 70 degrees Fahrenheit. To ensure warm soils in your home place seedling trays or pots near a heat vent, top of a refrigerator or other gentle heat source. Nurseries and garden shops also sell specially designed heat mats made for this purpose.
  • Containers– Take time to choose the right containers for the types of seeds you are growing. Many seedlings benefit from being transplanted at least once prior to planting in the ground. Plastic pots or six-packs can be reused and are easily cleaned. Always make sure all pots are cleaned and sterilized by rinsing with a 10% bleach solution. Peat pots are made from peat moss or paper waste fibers and need to be kept moist to guarantee the pots will completely decompose when planted in the garden. Peat pots are very popular, but can girdle root systems when fabric or the pot itself does not fully decompose in the ground.

Seedlings need to be “hardened-off” to acclimate to outdoor conditions and then transplanted outside when the danger of frost has passed. Hardening off is the process of acclimating your plants to outdoor weather, sun, wind, and changing temperatures. Placing seedlings outside on the east side of the home for a while each day before transplanting them can help. Seedlings will vary in size and shape. When thinning your seedlings choose those that are sturdy, not leggy or overgrown. Leggy, weak plants will transplant poorly and may die.

JoAnne Skelly
JoAnne Skelly

JoAnne: Starting Plants from Seeds

Plant, water, grow and hoe. These seem to be the steps to a successful garden. In northern Nevada, starting transplants from seed before the last frost date of May 15 is an excellent way to get the jump on the gardening season. When you start plants from seeds, you get transplants of the exact varieties you desire, rather than having your selection limited by what is available in a store.

A rule of thumb is to sow seeds indoors six weeks prior to planting outdoors. Supposedly you can start your seeds on March 6 for a May 15 planting date. But, anyone who has lived here awhile knows it could snow May 15, so there is flexibility to when you plant outside with later being better than earlier.

Growing seeds require a planting medium which may be vermiculite, soilless mixes or a variety of soil mixes. Germinating media should be fine, aerated and loose. It must be free of disease, insects and weed seeds. It should hold some water, but not keep delicate seedling roots too wet because they will get damping off or other diseases. An often recommended mixture is one-third sterilized soil, one-third sand, vermiculite or perlite and one-third peat moss. Small amounts of soil mix can be sterilized in the oven according to University of Arizona Cooperative Extension. They recommend putting the slightly damp mix in a heat-resistant container in an oven at about 250 degrees F. Use a meat or candy thermometer to make sure the soil gets to 180 degrees F for at least ½ hour. Do not overheat. They point out this mixture in the oven could smell pretty foul, so maybe just purchasing a sterilized mix from the nursery is a better idea.

The containers and tools you use to plant with should also be sterilized. Wash them to remove debris, then rinse in a solution of one part chlorine bleach to 10 parts water. You can purchase special trays, make your own or use recycled household containers. Be sure they drain well.

Read the label of the seed packet for exact directions. It will tell you if seeds need to be pre-germinated or other special treatments. For most seeds, fill the container to within ¾ inch of the top with moist growing medium. Firm the medium for a flat surface. Seeds are planted at a depth twice their diameter. Most should be lightly covered them with soil. Don’t plant too deeply or the seed will not germinate.

Try new varieties; explore the vegetable world and have fun!