What a nice spring we have been having in the southwest! I know I heard some of you complaining back a few weeks ago when the temperatures were in the 90’s. But the nights have not warmed up yet much at all. Right now, we are unseasonably cool. Enjoy it!! Plenty of time now to plant your summer pots and give them a great start before we do move into the true summer heat.
May’s Tips to Potted Garden Success
Let’s get going on our summer plantings
- Now is the ideal time to plant summer annuals, new perennials, veggies and herbs.
Some of my absolute summer favorites are Vinca, Pentas and Summer Snaps (Angelonia). Purslane is great in dry pots. Plant around Red Yucca for a stunning, low water pot. Never say, “I can’t grow anything in the summer.” Choose the right plants and make sure they have regular, consistent, daily water.
- As temperatures rise be sure to also increase the frequency and depth of watering for your citrus and roses
- Fertilize your citrus near NOW with a citrus fertilizer. (I love Arizona Best)
- Check your irrigation system for leaks.
May Rose Care
- Spray your roses with a jet blast of water three times a week. This is the best proactive method to keep your roses healthy.
- Put down mulch to keep soil from drying out.
- Be sure to dead head your roses this month to continue this bloom cycle while our weather is still favorable.
- Note: Always water your roses thoroughly the night before you fertilize.
- Week 1: Use one cup of organic fertilizer like Max Magic Mix or homemade compost. Scratch the dry fertilizer into the ground and water in again.
- Week 3 and every other week after: Use a water-soluble fertilizer with a hose applicator. Spray the rose leaves and buds as well as a thorough soaking of the soil.
- Week 4: Apply a dose of fish emulsion to help get the microorganisms going.
During the spring, the main rose ailments are aphids and mildew.
- Aphids: Use Bayer Rose Spray or Safer Insecticide once a week per bottle instructions to wipe them out.
- Mildew: Keep in check by using a good fungicide. It is best to fungicide as a preventative for mildew on a weekly basis, rather than waiting for the problem to show up. It’s harder to prevent damage once it’s started.
- Thrips: They attack the rose blooms and turn them brown. A simple way to keep them under control is to get a small plastic spray bottle with your favorite rose spray and spray the buds directly as they are starting to open. Do this once a week at least.
Water: Continue to water your roses deeply so all the soil is moist and water comes out of the drainage hole. Potted roses need deep watering every two days when in the 80’s and daily in the 90’s.
How can I be talking about summer flowers when this picture was just taken at the University of Arizona on March 15th? However, if our temperature trends continue, these pansies may be getting pretty tired by the time you read this update.
As you always hear me preach, I recommend that you do not plant summer flowers until the second half of April or later. Remember, I always talk about how long we ask our summer flowers to perform. If we plant late April, we won’t plant again until late October and that is six months. Planting in late March or the first week of April adds another month to that. We do want to plant before the summer heat arrives so the roots can get established before the soil warms up to summer levels.
You will have more options in the nursery too! For those of you chomping at the bit to plant sooner, just be prepared to add some new plants in August to refresh your pots if some of the plants are too tired to bloom or grow any longer.
Keep Up with Your Regular Flower Maintenance
It’s time to check your irrigation system
- NOTE: Newly planted pots need daily water.
- Review past water bills to track your usage – look for any obvious changes.
- Check your system for leaks.
- Do Not ASSUME… we need 1” of rain to be safe in turning off the irrigation for any length of time. Your pots will need water again in one to two days. Don’t forget to turn it back on!
- Adjust irrigation timers. As temperatures increase, so do the water needs of your garden. To give plants just the right amount, adjust the timer by increasing the number of days per week it operates, but not the number of minutes per cycle.
April Rose Care
Fertilize: Establish a regular fertilizing schedule for your roses starting this month with both organic and water soluble fertilizers:
- Monthly: Use Max Magic Mix or another organic fertilizer or homemade compost (about one cup per bush the first week
- Bi-weekly: Dilute your water soluble fertilizer (Miracle Grow, Peters, Scotts, etc) as the instructions state and shower your fertilizer using your hose.
- Additionally, be sure to apply a dose of fish emulsion once a month
- Be sure to water your roses thoroughly the night before you fertilize them and again after fertilizing.
Pests and Fungi: aphids and mildew:
- Spraying your roses off with water a couple of times a week will help reduce the aphid population. If a colony has gotten started, use Bayer Rose Spray or Safer Insecticide once a week per bottle instructions to wipe them out.
- When the weather gets warmer, the dreaded Thrips will appear. They attack the rose blooms and turn them brown. Using a small plastic spray bottle, spray the buds directly with your chosen insecticide above, as they begin to open. Do this at least once a week.
- Mildew can be kept in check by using a good fungicide. It is best to apply fungicide as a preventative for mildew on a weekly basis, rather than waiting for the problem to show up. It’s harder to prevent damage once it’s started.
Spring has “sprung” and in spite of the wind today, we know that upcoming days of 80 degree temperatures are in the forecaste. It’s easy to forget that not so long ago we were experiencing cold and rainy weather. Here is the top question I get asked along with my answer:
Is the danger of frost over?
I believe so! The last average freeze in Tucson is March 15. Right now the forecast through March 20 is 80/55. However, those living in the mountains or southern regions of Arizona, keep watching the night time temperatures and if it changes, be prepared to cover any tender new plantings if the forecast moves below 38 degrees I still suggest you wait to do any pruning until the end of them month. If you have any specific questions, please email me.
What to do in your potted garden this month:
- Watch for a surprise frost and cover tender annuals.
- If you have not fertilized your citrus, do so now.
- Check your irrigation system and be prepared to increase the frequency as temperatures
- Clean up leaf loss and cactus demise.
- Apply a pre-emergent if you have not already done so. Follow directions for watering this in if we still do not get any rain. This will help prevent weeds from popping up and save your energy to tend to your pots.
Rose Care (Information gathered with permission from The Tucson Rose Society’s Thrip Hater)
Start your program of fertilizing this month
- An organic fertilizer like Max Magic Mix or homemade compost on one week (about a cup per bush)
- Two weeks later fertilize with Rapid-Gro or Miracle-Gro for Roses.
- Once a month apply a dose of fish emulsion to help get the micro-organisms going.
- Water your roses thoroughly the night before you fertilize them
Watering Potted Roses:
- If daytime temperatures are in the 70’s, water every 3 – 4 days.
- When temperatures rise to the 80’s, water every 2-3 days.
- Water so the water runs out of the hole in the bottom of the pot.
- If you have flowers planted in your rose pots, you will have to adjust your watering to meet the needs of the flowers. However, established flowers should be fine with the above schedule.
Pest Threat: Aphids and Mildew
Aphids: Jet Spray roses off with water a couple of times a week. If a colony has gotten started, use Bayer or Safer Rose Spray once a week per bottle instructions
Mildew: Spray Funginex as a preventative for Mildew on a weekly basis, rather than waiting for the problem to show up.
Thrips: When the weather gets warmer the dreaded Thrips will appear. They attack the rose blooms and turn them brown. A simple way to keep them under control is to get a small plastic spray bottle and fill it with Bayer or Safer Rose Spray or Orthinex aerosol. Spray the buds directly once a week as they are starting to open. Watering:—Reprinted from the March 20
Note: If you love your potted roses or have roses in the ground, you want to become a member of the Tucson Rose Society. It is inexpensive ($20 a year) and you receive great information from them and have many rose experts and information at your fingertips. Visit Tucson Rose Society for more information.
You will want to finish pruning your roses by early-February so that they can rest for a couple weeks before our early spring tells them to start growing! Follow these steps for a healthy spring bloom! The same instructions apply for all Hybrid Tea and Floribunda roses. Pruning Use bypass pruners that work similar to scissors. Anvil-type pruners will crush your rose stems.
- Prune the rose bush down to a height of 8-12”. Yes – this will remove ½ to 2/3 of the plant.
- Remove any dead canes and small twiggy growth.
- Remove any canes that are crossing through the middle of the bush or rubbing against other canes. This also opens up the center of the plant. You want your bush to have a “vase” shape to it.
- Make your cuts about 1/4 inch above a bud eye that is facing out from the center of the bush.
- Strip all leaves from the canes.
- Remove all the old mulch and dead leaves and throw them in the trash, not your compost pile.
- Dead leaves can often have mildew spores and other diseases on them that can infest your compost pile and create problems later on.
- Apply both a pesticide and a fungicide to your pruned roses and the ground around the plants. Fungus spores such as mildew can live through the winter in your soil.
- Seal pruned canes larger than a pencil with carpenter’s glue (it’s waterproof) to protect against cane borers.
- Re-potting: Check your roses in pots to see if they need to be repotted. How low is the soil in the pot? If it is lower than 3 inches below the rim, it is probable that the soil has become too compacted and the tiny hair roots can’t get the oxygen they need. Lift the entire plant out of the pot, loosen any soil around the root ball and repot in fresh potting soil.
Water and Feed
- Do not fertilize your roses until mid-February.
- Continue to water your ground-planted roses, once or twice a week depending on the daytime temperatures. Be sure you are deep watering to a depth of 18 to 24 inches.
- Roses in pots typically need to be watered more often than roses in the ground, approximately providing them with a deep watering every 4 days.
Question? Leave a comment below for Marylee today!
January is is a wonderful period of time in the desert. The holidays are over and soon all the decorations will be away if they are not done already. Unless you have roses, there is not a lot you need to do in your potted gardens. So be sure to seek out the warmer days and enjoy the colorful gardens you have created.
January’s Container Garden Checklist
- Continue to deadhead all flowers low on the stem or to new growth.
- Keep up with your water soluble fertilizer routine every 2 weeks, especially if you have neglected this over the holidays.
- Prepare to cut back your roses this month. I will put out another update on how to do this next week.
- Continue to cover tender annuals, plants and succulents when there are freeze warnings.
Update on book publishing – Getting Potted in the Desert
Many of you know I have been working on a long overdue book on container gardening in the desert. We hope to have it out by early March. I am planning to self publish so stay tuned right here to find out when it is ready. My goal for the book is for you to be able to have a potted garden, here in the desert. One that for many of you will remind you of your garden ‘back home.’
Also, check out my upcoming classes at the Tucson Botanical Gardens in the sidebar to the right.
If you have missed the warning today through Sunday:
There is a freeze warning for the Tucson/Pima County region. Please check your local forecast for specifics. Details online can be found at weather.gov/tucson.
Frost Protection Checklist
— Water all potted plants
— Cover the entire plant area with frost cloths, sheets, or light blankets. Do not use towels or plastic.
— Secure the cloth inside the pot at the soil level with rocks or clothespins.
— Remove covering during the day if you can and cover again until danger of frost is over.
If you have any questions, please email me and I will try to get back to you quickly.
Prepare for the coming holidays with a final spruce up of your pots. The picture above has reds for those celebrating Christmas but are not so committed to being a ‘red all over’ theme that no matter what holiday you might celebrate, these pots will be a cheerful addition to any entry. There is an added benefit of a lettuce mix in bright green and red that will easily find its way into your daily salads.
Don’t be afraid to add more flowers to your desert potted garden this month. You can continue to plant all winter long. Just hold off if the temperatures approach the freezing mark as it will be hard for the young plants to get off to a good start. Typically these low temperatures only last a week and you can start planting again as long as the night time temperatures are in the 40’s.
December’s Desert Potted Garden Checklist:
- Continue to plant successive plantings of lettuce, spinach, chard, and other fast-maturing winter greens.
- Snip petunias to encourage them to branch and spread and reduce the stickiness and ‘ickiness’ of maturing plants. Cut the ends off of stems to encourage side branching. This will promote abundant flowering and more compact plants.
- Remove the old blooms from geranium, cyclamen, calendula and other winter flowers as they fade by cutting them off with sharp scissors or hand pruners. This will also increase flower production.
- Use a bi-weekly spray application of a water soluble fertilizer on all flowering plants to encourage growth and a continual show of flowers as seen in the picture below.
Potted Roses – General Notes:
- Water potted roses two to three times each week.
- If you purchased bare root roses and have planted them in pots, it is best to move them to a protected area if the weather gets below freezing.
- Begin now to plan for roses that will need replacing or relocating.
- Pruning needs to be completed by Feb 10, so enjoy a month of relaxation until then!
Special Attention in December <<FREEZE WARNINGS>>
- Check your weather forecast for freeze warnings
- Cover the tips of sensitive columnar cacti with Styrofoam cups
- Use frost cloth or a blanket to cover aloes, citrus, and other sensitive plants when temperatures drop below 28°F